Red Hat Enterprise Linux 6/7/8/9 X.org X11 Server/TigerVNC compCheckRedirect uninitialized pointer

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

Summaryinfo

A vulnerability was found in Red Hat Enterprise Linux 6/7/8/9. It has been classified as critical. The affected element is the function compCheckRedirect of the component X.org X11 Server/TigerVNC. The manipulation leads to uninitialized pointer. This vulnerability is traded as CVE-2025-26599. An attack has to be approached locally. There is no exploit available.

Detailsinfo

A vulnerability was found in Red Hat Enterprise Linux 6/7/8/9. It has been rated as critical. This issue affects the function compCheckRedirect of the component X.org X11 Server/TigerVNC. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. Using CWE to declare the problem leads to CWE-824. The product accesses or uses a pointer that has not been initialized. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

An access to an uninitialized pointer flaw was found in X.Org and Xwayland. The function compCheckRedirect() may fail if it cannot allocate the backing pixmap. In that case, compRedirectWindow() will return a BadAlloc error without validating the window tree marked just before, which leaves the validated data partly initialized and the use of an uninitialized pointer later.

It is possible to read the advisory at access.redhat.com. The identification of this vulnerability is CVE-2025-26599 since 02/12/2025. The exploitation is known to be easy. Attacking locally is a requirement. Technical details of the vulnerability are known, but there is no available exploit. The pricing 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-2025-5424) and CERT Bund (WID-SEC-2025-0435). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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: Uninitialized pointer
CWE: CWE-824 / CWE-908
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: Confirmed

CVE: CVE-2025-26599 (🔍)
GCVE (CVE): GCVE-0-2025-26599
GCVE (VulDB): GCVE-100-296819
EUVD: 🔍
CERT Bund: WID-SEC-2025-0435 - X.Org X11: Mehrere Schwachstellen ermöglichen nicht näher spezifizierte Auswirkungen, möglicherweise Codeausführung

Entryinfo

Created: 02/25/2025 18:24
Updated: 06/06/2026 09:25
Changes: 02/25/2025 18:24 (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 09:25 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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