CVE-2025-26601

CVE-2025-26601 is a high-severity vulnerability in Redhat Enterprise Linux with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Description

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.

Frequently asked questions

What is CVE-2025-26601?
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.
How severe is CVE-2025-26601?
CVE-2025-26601 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-26601 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-26601?
CVE-2025-26601 primarily affects Redhat Enterprise Linux. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-26601?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-26601 have an EU (EUVD) identifier?
Yes. CVE-2025-26601 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5426.
When was CVE-2025-26601 published?
CVE-2025-26601 was published on 2025-02-25 and last updated on 2026-06-29.

References

Affected products (6)

More vulnerabilities in Redhat Enterprise Linux

All CVEs affecting Redhat Enterprise Linux →

Other CWE-416 (Use After Free) vulnerabilities

Browse all CWE-416 (Use After Free) vulnerabilities →