CVE-2026-34001
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-34001 is a high-severity Expired Pointer Dereference (CWE-825) vulnerability in Redhat (inferred from references). Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 18th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-34001, published on 2026-04-23, is a use-after-free vulnerability (CWE-825) in the X.Org X server. The flaw resides in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence() function, affecting the X11 server component.
Local attackers with low privileges can exploit this issue without user interaction, as indicated by the CVSS v3.1 vector AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (base score 7.8). Successful exploitation triggers a server crash and enables memory corruption, potentially resulting in denial of service or further system compromise.
Red Hat has released multiple errata addressing this vulnerability, including RHSA-2026:10739, RHSA-2026:11352, RHSA-2026:11369, RHSA-2026:11388, and RHSA-2026:11656, which provide patched packages for affected systems.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-25230
Vulnerability Data
A flaw was found in the X.Org X server. This use-after-free vulnerability occurs in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence() function. An attacker with access to the X11 server can exploit this without user interaction, leading to…
more
a server crash and potentially enabling memory corruption. This could result in a denial of service or further compromise of the system.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation (including fuzzing, static analysis, and dynamic memory checkers) directly finds expired-pointer dereferences before deployment.
Secure engineering principles applied during design and implementation can mandate memory-safe allocation, ownership, and deallocation patterns that structurally avoid use of expired pointers.
Process isolation confines the effects of a use-after-free within a single address space, reducing cross-process impact.
Memory-protection mechanisms limit the blast radius when an expired pointer is dereferenced, even though they do not stop the coding flaw itself.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure-development practices directly prevent coding errors such as use-after-free while one CWE contributes only modestly to the full control.
Lifecycle management includes secure development and maintenance phases that reduce memory-safety defects.
Vulnerability identification processes can discover use-after-free flaws via scanning or analysis.
Routine patching and replacement can eliminate known instances of expired-pointer bugs.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect use-after-free issues, but removing this weakness alone does not fulfill the testing control.
Secure development lifecycle practices can include pointer lifetime and memory-management rules that reduce expired-pointer dereferences.
Application security requirements may mandate safe memory handling, but eliminating this single weakness does not satisfy the broader requirement.
Secure architecture and engineering principles can prescribe memory-safety patterns, yet fixing only this weakness does not achieve the control.
Secure coding standards directly address pointer lifetime and deallocation discipline, substantially mitigating expired-pointer dereference.
Change-management processes can require re-validation of memory safety after modifications, indirectly reducing the weakness.