A flaw was found in libxslt where the attribute type, atype, flags are modified in a way that corrupts internal memory management. When XSLT functions, such as the key() process, result in tree fragments, this corruption prevents the proper cleanup of ID attributes. As a result, the system may access freed memory, causing crashes or enabling attackers to trigger heap corruption.
Credits
Red Hat would like to thank Sergei Glazunov (Google Project Zero) for reporting this issue.
