X.org libXtst up to 1.2.5 parse_reply_call_callback infinite loop

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.33

Summaryinfo

A vulnerability classified as problematic was found in X.org libXtst up to 1.2.5. This affects the function parse_reply_call_callback. Executing a manipulation can lead to infinite loop. This vulnerability is tracked as CVE-2026-109088. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in X.org libXtst up to 1.2.5. It has been declared as problematic. This vulnerability affects the function parse_reply_call_callback. The manipulation with an unknown input leads to a infinite loop vulnerability. The CWE definition for the vulnerability is CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. As an impact it is known to affect availability. CVE summarizes:

A malicious X server could send malformed  RECORD EnableContext reolies that can cause a X client using the parse_reply_call_callback function in libXtst before 1.2.6 to enter a endless loop.

The advisory is available at gitlab.freedesktop.org. This vulnerability was named CVE-2026-109088 since 10/12/2026. The exploitation appears to be easy. The attack can be initiated remotely. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 1.2.6 eliminates this vulnerability.

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Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (suse): 🔒

CVSSv2info

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

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libXtst 1.2.6

Timelineinfo

10/12/2026 CVE reserved
10/27/2026 +15 days Advisory disclosed
10/27/2026 +0 days VulDB entry created
10/27/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: x.org

Advisory: gitlab.freedesktop.org
Status: Confirmed

CVE: CVE-2026-109088 (🔒)
GCVE (CVE): GCVE-0-2026-109088
GCVE (VulDB): GCVE-100-427462

Entryinfo

Created: 10/27/2026 17:57
Changes: 10/27/2026 17:57 (63)
Complete: 🔍
Cache ID: 216::103

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