CVE intelligence and bounded remediation
CVE-2025-26601 — A use-after-free flaw was found in X.Org and Xwayland
A use-after-free flaw was found in X.Org and Xwayland. When changing an alarm, the values of the change mask are evaluated one after the other, changing the trigger values as requested, and eventually, SyncInitTrigger() is called. If one of the changes triggers an error, the function will return early, not adding the new sync object, possibly causing a use-after-free when the alarm eventually triggers.
- Severity
- High
- CVSS
- 7.8 (3.1)
- Published
- 2025-02-25
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-416
Affected products
- tigervnc / tigervnc
- x.org / x_server
- x.org / xwayland
- redhat / enterprise_linux / 7.0
- redhat / enterprise_linux / 8.0
- redhat / enterprise_linux / 9.0
Matched remediation archetype
Use-after-free, double free, and expired resource use
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace ownership, references, callbacks, asynchronous tasks, and teardown paths around the affected object or resource.
- Identify reachable inputs and timing or state transitions that can release the object while references remain.
- Confirm affected builds, allocators, feature flags, architectures, and process privileges.
Remediate safely
- Apply the maintained ownership or lifetime fix and rebuild all artifacts containing the affected native code.
- Use explicit ownership, safe reference management, cancellation and join semantics, and idempotent teardown.
- Add deterministic lifetime tests plus isolated sanitizer and concurrency coverage for shutdown and error paths.
Authoritative sources
Complete CVE record and remediation plan
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