HIGHVulnerability
CVE-2026-50257
A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence(). A client that sets up multiple fence triggers can trigger a use-after-free function pointer call. An attacker would connect to the X server to set up a fence and await that fence, then a second X connection destroys the fence, causing the use-after-free. This may be used to crash the server, or for privilege escalation if the X server runs as root.
Properties
- severity
- HIGH
- score
- 7.8
- cve_id
- CVE-2026-50257
- vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- published_at
- 2026-06-05T12:16:38.907
- last_modified
- 2026-08-05T13:23:29.603
Related Entities (8)
AFFECTS_PRODUCT (6)
→[Product]
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HAS_WEAKNESS (1)
→[Weakness]Use After Free
DESCRIBED_BY (1)
→[Source]NVD
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