A flaw was reported [1] in libpurple's SILC protocol plugin, and all software which uses SILC via libpurple. The gmarkupescapetext() function, when called on strings that have not been verified as valid UTF-8, will read past the end of the string and eventually segfault for certain sequences in some versions of Glib2. The behaviour of this function was undefined, and because it depends on the particular version of Glib2 in use, it is unknown what the complete ramifications of the flaw is, however it has been verified that an untrusted user could remotely crash a libpurple client via specially crafted SILC messages.

This flaw is believed to affect all versions of libpurple up to and including 2.10.0. This has been corrected in the upstream git repository [2].

[1] http://developer.pidgin.im/ticket/14636 [2] http://developer.pidgin.im/viewmtn/revision/diff/be5e66abad2af29604bc794cc4c6600ab12751f3/with/7eb1f6d56cc58bbb5b56b7df53955d36b9b419b8

The msnslpprocessmsg function in libpurple/protocols/msn/slpcall.c in the MSN protocol plugin in libpurple 2.6.0 and 2.6.1, as used in Pidgin before 2.6.2, allows remote attackers to cause a denial of service (application crash) via a handwritten (aka Ink) message, related to an uninitialized variable and the incorrect "UTF16-LE" charset name.