USN-251-1: libtasn vulnerability
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Ubuntu Security Notice USN-251-1 February 16, 2006
libtasn1-2 vulnerability
CVE-2006-0645
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A security issue affects the following Ubuntu releases:
Ubuntu 4.10 (Warty Warthog)
Ubuntu 5.04 (Hoary Hedgehog)
Ubuntu 5.10 (Breezy Badger)
The following packages are affected:
libtasn1-2
libgnutls10
libgnutls11
The problem can be corrected by upgrading the affected package to
the following versions:
Ubuntu 4.10:
libtasn1-2: 0.2.7-2ubuntu0.1
libgnutls10: 1.0.4-3ubuntu1.2
Ubuntu 5.04:
libtasn1-2: 0.2.10-4ubuntu0.0.5.04.1
libgnutls11: 1.0.16-13ubuntu0.2
Ubuntu 5.10:
libtasn1-2: 0.2.10-4ubuntu0.1
libgnutls11: 1.0.16-13.1ubuntu1.1
It is highly recommended to restart your computer after a standard
system upgrade to effect the necessary changes. If you cannot afford
to do that then you need to restart all server processes which use
TLS or SSL.
Details follow:
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.



