A vulnerability labeled as critical has been found in Xmlsoft libxml2 up to 2.15.3 . The affected element is the function usershell of the component Xmlcatalog Utility . The manipulation results in stack-based buffer overflow. This vulnerability is reported as CVE-2026-11979 . The attack can be launched remotely. No exploit exists. The presence of this vulnerability remains uncertain at this time. The affected component should be upgraded.