Tim Starling discovered that libthai, a set of Thai language support routines, is vulnerable of integer/heap overflow. This vulnerability could allow an attacker to run arbitrary code by sending a very long string.
For the oldstable distribution (etch), this problem has been fixed in version 0.1.6-1+etch1.
For the stable distribution (lenny), this problem has been fixed in version 0.1.9-4+lenny1.
For the testing distribution (squeeze), and the unstable distribution (sid), this problem will be fixed soon.
We recommend that you upgrade your libthai package.