Red Hat Enterprise Linux 6/7/8/9 X.org X11 Server/TigerVNC use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.8$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical has been found in Red Hat Enterprise Linux 6/7/8/9. Affected by this vulnerability is an unknown functionality of the component X.org X11 Server/TigerVNC. The manipulation leads to use after free. This vulnerability is listed as CVE-2025-26594. The attack must be carried out locally. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Red Hat Enterprise Linux 6/7/8/9. This issue affects some unknown processing of the component X.org X11 Server/TigerVNC. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A use-after-free flaw was found in X.Org and Xwayland. The root cursor is referenced in the X server as a global variable. If a client frees the root cursor, the internal reference points to freed memory and causes a use-after-free.

The advisory is shared at access.redhat.com. The identification of this vulnerability is CVE-2025-26594 since 02/12/2025. The exploitation is known to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/06/2026).

The vulnerability scanner Nessus provides a plugin with the ID 216902 (SUSE SLED15 / SLES15 / openSUSE 15 Security Update : xorg-x11-server (SUSE-SU-2025:0730-1)), which helps to determine the existence of the flaw in a target environment.

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 databases at Tenable (216902), EUVD (EUVD-2025-5370) and CERT Bund (WID-SEC-2025-0435). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • Gentoo Linux
  • IGEL OS
  • SUSE openSUSE
  • RESF Rocky Linux
  • OpenBSD OpenBSD
  • Dell NetWorker
  • Dell Avamar
  • Open Source X.Org X11
  • Open Source Xming
  • Dell PowerProtect Data Domain

Productinfo

Type

Vendor

Name

Version

License

Website

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

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 216902
Nessus Name: SUSE SLED15 / SLES15 / openSUSE 15 Security Update : xorg-x11-server (SUSE-SU-2025:0730-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

02/12/2025 🔍
02/25/2025 +13 days 🔍
02/25/2025 +0 days 🔍
06/06/2026 +466 days 🔍

Sourcesinfo

Vendor: redhat.com

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2025-26594 (🔍)
GCVE (CVE): GCVE-0-2025-26594
GCVE (VulDB): GCVE-100-296813
EUVD: 🔍
CERT Bund: WID-SEC-2025-0435 - X.Org X11: Mehrere Schwachstellen ermöglichen nicht näher spezifizierte Auswirkungen, möglicherweise Codeausführung

Entryinfo

Created: 02/25/2025 18:22
Updated: 06/06/2026 03:43
Changes: 02/25/2025 18:22 (63), 02/27/2025 12:16 (2), 03/10/2025 14:28 (1), 06/16/2025 17:11 (1), 07/24/2025 18:47 (7), 06/06/2026 03:43 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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