high7.8
CVE-2026-50260
A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter().
Impact
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.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| X.Org | X Server | before 21.1.23 |
| X.Org | Xwayland | before 24.1.12 |
| Redhat | Enterprise Linux | Versions 7.0, 8.0, 9.0, 10.0 |
Weakness classification
References
- NVD record
- CVE.org record
- https://access.redhat.com/errata/RHSA-2026:26562
- https://access.redhat.com/errata/RHSA-2026:26566
- https://access.redhat.com/errata/RHSA-2026:26590
- https://access.redhat.com/errata/RHSA-2026:26610
- https://access.redhat.com/errata/RHSA-2026:26709
- https://access.redhat.com/errata/RHSA-2026:28923
- https://access.redhat.com/errata/RHSA-2026:29844
- https://access.redhat.com/errata/RHSA-2026:36083
- https://access.redhat.com/errata/RHSA-2026:36085
- https://access.redhat.com/errata/RHSA-2026:36086
- https://access.redhat.com/errata/RHSA-2026:36087
- https://access.redhat.com/errata/RHSA-2026:36632
- https://access.redhat.com/errata/RHSA-2026:36633
- https://access.redhat.com/errata/RHSA-2026:36634
- https://access.redhat.com/errata/RHSA-2026:36768
- https://access.redhat.com/errata/RHSA-2026:36791
- https://access.redhat.com/errata/RHSA-2026:36792
- https://access.redhat.com/errata/RHSA-2026:36798
- https://access.redhat.com/errata/RHSA-2026:38502
- https://access.redhat.com/errata/RHSA-2026:38810
- https://access.redhat.com/errata/RHSA-2026:46377
- https://access.redhat.com/errata/RHSA-2026:46382
- https://access.redhat.com/errata/RHSA-2026:46385
- https://access.redhat.com/errata/RHSA-2026:46392
- https://access.redhat.com/errata/RHSA-2026:46456