Chen Baozi

**Name of the Vulnerable Software and Affected Versions** Xen versions 4.4.x **Description** The issue is related to the improper context switching of the CNTKCTL EL1 register when Xen is running on an ARM system. This allows local guest users to modify the hardware timers, which can cause a denial of service (crash) via unspecified vectors. **Recommendations** For Xen version 4.4.x, consider applying a patch or fix that properly handles the context switching of the CNTKCTL EL1 register to prevent local guest users from modifying the hardware timers and causing a denial of service.