DSA-061-1 gnupg -- printf format attack

Debian Security Advisory

DSA-061-1 gnupg -- printf format attack

Date Reported:

16 Jun 2001

Affected Packages:

gnupg

Vulnerable:

Yes

Security database references:

In the Bugtraq database (at SecurityFocus): BugTraq ID 2797.
In Mitre's CVE dictionary: CVE-2001-0522.

More information:

The version of GnuPG (GNU Privacy Guard, an OpenPGP implementation) as distributed in Debian GNU/Linux 2.2 suffers from two problems:

1. fish stiqz reported on bugtraq that there was a printf format problem in the do_get() function: it printed a prompt which included the filename that was being decrypted without checking for possible printf format attacks. This could be exploited by tricking someone into decrypting a file with a specially crafted filename.
2. The second bug is related to importing secret keys: when gnupg imported a secret key it would immediately make the associated public key fully trusted which changes your web of trust without asking for a confirmation. To fix this you now need a special option to import a secret key.

Both problems have been fixed in version 1.0.6-0potato1.

Fixed in:

Debian GNU/Linux 2.2 (potato)

Source:

http://security.debian.org/dists/stable/updates/main/source/gnupg_1.0.6-0potato1.diff.gz

http://security.debian.org/dists/stable/updates/main/source/gnupg_1.0.6-0potato1.dsc

http://security.debian.org/dists/stable/updates/main/source/gnupg_1.0.6.orig.tar.gz

Alpha:

http://security.debian.org/dists/stable/updates/main/binary-alpha/gnupg_1.0.6-0potato1_alpha.deb

ARM:

http://security.debian.org/dists/stable/updates/main/binary-arm/gnupg_1.0.6-0potato1_arm.deb

Intel IA-32:

http://security.debian.org/dists/stable/updates/main/binary-i386/gnupg_1.0.6-0potato1_i386.deb

Motorola 680x0:

http://security.debian.org/dists/stable/updates/main/binary-m68k/gnupg_1.0.6-0potato1_m68k.deb

PowerPC:

http://security.debian.org/dists/stable/updates/main/binary-powerpc/gnupg_1.0.6-0potato1_powerpc.deb

Sun Sparc:

http://security.debian.org/dists/stable/updates/main/binary-sparc/gnupg_1.0.6-0potato1_sparc.deb

MD5 checksums of the listed files are available in the original advisory.