X.Org Server/xwayland X11 Resource Proc-SProcXResQueryClientIds buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00+

Summaryinfo

A vulnerability, which was classified as critical, was found in X.Org Server and xwayland. Impacted is the function Proc-SProcXResQueryClientIds of the component X11 Resource. The manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2026-109904. The attack may be launched remotely. There is no exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as critical has been found in X.Org Server and xwayland (affected version not known). Affected is the function Proc-SProcXResQueryClientIds of the component X11 Resource. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A buffer overread caused by an integer-overflow in Proc/SProcXResQueryClientIds in X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by attackers on authenticated X clients to crash the server or leak out information.

The advisory is available at gitlab.freedesktop.org. This vulnerability is traded as CVE-2026-109904 since 10/13/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit.

Applying the patch ff754b812597177412f2e2fa2b1dd1eecbeb75cf is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-125273). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: ff754b812597177412f2e2fa2b1dd1eecbeb75cf

Timelineinfo

10/13/2026 CVE reserved
11/13/2026 +31 days Advisory disclosed
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: x.org

Advisory: gitlab.freedesktop.org
Status: Confirmed

CNA: suse
CVE: CVE-2026-109904 (🔒)

GCVE (CVE): GCVE-0-2026-109904
GCVE (VulDB): GCVE-100-436914
EUVD: 🔒

Entryinfo

Created: 11/13/2026 12:01
Updated: 11/13/2026 13:12
Changes: 11/13/2026 12:01 (66), 11/13/2026 13:12 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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