PatchTheCVExwayland vulnerabilities and fixes
Recent CVEs affecting xwayland, with upgrade or downgrade steps. 11 tracked.
xwayland has 11 tracked vulnerabilities, 0 critical. A fixed release or vendor patch exists for 11. Most recent: 2026-07-08. Highest priority: CVE-2026-55999 (score 36/100).
- CVE-2026-50261 HIGH 7.8 UPGRADE UPGRADE A use-after-free flaw was found in the X.Org X server and Xwayland in SyncChangeCounter()
- CVE-2026-50260 HIGH 7.8 UPGRADE UPGRADE A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter()
- CVE-2026-50259 HIGH 7.8 UPGRADE UPGRADE A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland
- CVE-2026-50258 HIGH 7.8 UPGRADE UPGRADE A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland
- CVE-2026-50257 HIGH 7.8 UPGRADE UPGRADE A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence()
- CVE-2026-50256 HIGH 7.8 UPGRADE UPGRADE A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland
- CVE-2026-50263 MEDIUM 5.5 UPGRADE UPGRADE A use-after-free flaw was found in the X.Org X server and Xwayland in CreateSaverWindow()
- CVE-2026-50262 MEDIUM 5.5 UPGRADE UPGRADE An out-of-bounds read flaw was found in the X.Org X server and Xwayland in __glXDisp_ChangeDrawableAttributes(
- CVE-2026-50264 HIGH 7.8 UPGRADE UPGRADE An out-of-bounds write flaw was found in the X.Org X server and Xwayland in DRIGetBuffers/DRIGetBuffersWithFor
- CVE-2026-55999 HIGH 8.5 UPGRADE UPGRADE Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before 21.2.24 and
- CVE-2026-56000 HIGH 7.8 UPGRADE UPGRADE Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and
FAQ
How do I fix xwayland vulnerabilities?
Open the CVE for your version, check the affected range, then follow the listed action: upgrade to the fixed release, or downgrade or mitigate if no fix exists yet. Commands for each OS are shown on every CVE page.
Is xwayland being exploited right now?
None of the tracked xwayland CVEs are on the CISA Known Exploited Vulnerabilities list at the moment. This is checked every 20 minutes.
Which xwayland CVE should I patch first?
CVE-2026-55999 currently ranks highest (36/100): Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before 21.2.24 and .