USN-251-1: libtasn vulnerability

Releases

• Ubuntu 5.10
• Ubuntu 5.04
• Ubuntu 4.10

Details

Evgeny Legerov discovered a buffer overflow in the DER format decoding
function of the libtasn library. This library is mainly used by the
GNU TLS library; by sending a specially crafted X.509 certificate to a
server which uses TLS encryption/authentication, a remote attacker
could exploit this to crash that server process and possibly even
execute arbitrary code with the privileges of that server.

In order to fix the vulnerability in libtasn, several internal
function signatures had to be changed; some of these functions are
used by the GNU TLS library, so that library needs to be updated as
well.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 5.10

• libgnutls10 -
• libgnutls11 -
• libtasn1-2 -

Ubuntu 5.04

• libgnutls10 -
• libgnutls11 -
• libtasn1-2 -

Ubuntu 4.10

• libgnutls10 -
• libgnutls11 -
• libtasn1-2 -

In general, a standard system update will make all the necessary changes.

References

• CVE-2006-0645