CVE-2026-50260
7.8 HIGHA use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter()
Published: 2026-06-05 · Last updated: 2026-06-11
Severity and scoring
- CVSS
- 7.8 HIGH
- Vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-416
Affected products
| Vendor | Product |
|---|---|
| redhat | enterprise_linux, x_server, xwayland |
| x.org | enterprise_linux, x_server, xwayland |
Description
A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter(). A client that sets up multiple SyncCounters and awaits on those triggers can trigger a use-after-free when destroying those counters via a second client connection. This may be used to crash the server, or for privilege escalation if the X server runs as root.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2026-50260
- [Other]https://access.redhat.com/security/cve/CVE-2026-50260
- [Other]https://bugzilla.redhat.com/show_bug.cgi?id=2485385
- [Patch]https://gitlab.freedesktop.org/xorg/xserver/-/commit/f5abfb61994471023d8c6470428c8e30c411cc0b
- [Vendor advisory]https://lists.x.org/archives/xorg-announce/2026-June/003702.html
- [Other]https://redhat.atlassian.net/browse/PSIRTSUPT-16950
Related CVEs
Same vendor
- CVE-2026-50263 — A use-after-free flaw was found in the X.Org X server and Xwayland in CreateSaverWindow() (5.5 MEDIUM)
- CVE-2026-50259 — A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland (7.8 HIGH)
- CVE-2026-50258 — A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland (7.8 HIGH)
- CVE-2026-50257 — A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence() (7.8 HIGH)
- CVE-2026-50256 — A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland (7.8 HIGH)
Same CWE
- CVE-2026-12035 — Use after free in Views in Google Chrome on Windows prior to 149.0.7827.115 allowed a remote attacker to potentially exploit heap corrupt...
- CVE-2026-12029 — Use after free in Video in Google Chrome on Windows prior to 149.0.7827.115 allowed a remote attacker who had compromised the renderer pr... (8.3 HIGH)
- CVE-2026-12028 — Use after free in GPU in Google Chrome on Android prior to 149.0.7827.115 allowed a remote attacker who had compromised the renderer proc... (8.3 HIGH)
- CVE-2026-12023 — Use after free in GPU in Google Chrome on Mac prior to 149.0.7827.115 allowed a remote attacker who had compromised the renderer process ... (8.3 HIGH)
- CVE-2026-12020 — Use after free in Autofill in Google Chrome on Mac prior to 149.0.7827.115 allowed a remote attacker to potentially exploit heap corrupti... (8.8 HIGH)