CVE-2026-34001 | X.org X Server miSyncTriggerFence expired pointer dereference (EUVD-2026-25230)

VDB-359149 · CVE-2026-34001 · EUVD-2026-25230 X.ORG X SERVER MISYNCTRIGGERFENCE EXPIRED POINTER DEREFERENCE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.8 $0-$5k 2.85 Summaryinfo A vulnerability was found in X.org X Server. It has been rated as critical. Affected is the function miSyncTriggerFence. This manipulation causes expired pointer dereference. The identification of this vulnerability is CVE-2026-34001. The attack can only be executed locally. There is no exploit available. Detailsinfo A vulnerability has been found in X.org X Server (version unknown) and classified as critical. Affected by this vulnerability is the function miSyncTriggerFence. The manipulation with an unknown input leads to a expired pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-825. The product dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is: 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 a server crash and potentially enabling memory corruption. This could result in a denial of service or further compromise of the system. The advisory is shared at access.redhat.com. This vulnerability is known as CVE-2026-34001 since 03/25/2026. The exploitation appears to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/23/2026). There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25230). Productinfo Vendor X.org Name X Server License open-source Website Vendor: https://www.x.org/ CPE 2.3info 🔒 CPE 2.2info 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 7.8 VulDB Meta Temp Score: 7.8 VulDB Base Score: 7.8 VulDB Temp Score: 7.8 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 7.8 CNA Vector (redhat): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Expired pointer dereference CWE: CWE-825 CAPEC: 🔒 ATT&CK: 🔒 Physical: Partially Local: Yes Remote: No Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 03/25/2026 CVE reserved 04/23/2026 +28 days Advisory disclosed 04/23/2026 +0 days VulDB entry created 04/23/2026 +0 days VulDB entry last update Sourcesinfo Vendor: x.org Advisory: access.redhat.com Status: Confirmed CVE: CVE-2026-34001 (🔒) GCVE (CVE): GCVE-0-2026-34001 GCVE (VulDB): GCVE-100-359149 EUVD: 🔒 Entryinfo Created: 04/23/2026 18:13 Updated: 04/23/2026 19:29 Changes: 04/23/2026 18:13 (60), 04/23/2026 19:29 (1) Complete: 🔍 Cache ID: 99:BDE:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸