Multiple integer overflows in the PyOS_vsnprintf function in Python/mysnprintf.c in Python 2.5.2 and earlier allow context-dependent attackers to cause a denial of service (memory corruption) or have unspecified other impact via crafted input to string formatting operations. NOTE: the handling of certain integer values is also affected by related integer underflows and an off-by-one error.

More... (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2008-3144)