A heap-based buffer overflow problem was found in glib through an incorrect calculation of buffer size in the g_escape_uri_string() function. If the string to escape contains a very large number of unacceptable characters (which would need escaping), the calculation of the length of the escaped string could overflow, leading to a potential write off the end of the newly allocated string.
A flaw was found in libxml2's xmlBuildQName function, where integer overflows in buffer size calculations can lead to a stack-based buffer overflow. This issue can result in memory corruption or a denial of service when processing crafted input.