OpenClaw up to 2026.5.5 Mattermost failing open

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.7$0-$5k3.51

Summaryinfo

A vulnerability labeled as problematic has been found in OpenClaw up to 2026.5.5. The affected element is an unknown function of the component Mattermost Handler. Such manipulation leads to failing open. This vulnerability is uniquely identified as CVE-2026-53837. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in OpenClaw up to 2026.5.5. It has been rated as problematic. Affected by this issue is an unknown part of the component Mattermost Handler. The manipulation with an unknown input leads to a failing open vulnerability. Using CWE to declare the problem leads to CWE-636. When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that are available, such as selecting the weakest encryption algorithm or using the most permissive access control restrictions. Impacted is integrity. CVE summarizes:

OpenClaw before 2026.5.6 contains an improper access control vulnerability in Mattermost event handlers that fails to validate channel type metadata. Attackers can bypass intended DM policy decisions by sending crafted Mattermost events missing channel type information to process restricted content.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-53837 since 06/10/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 2026.5.6 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

Website

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: 3.7
VulDB Meta Temp Score: 3.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.7
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Failing open
CWE: CWE-636
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: OpenClaw 2026.5.6

Timelineinfo

06/10/2026 CVE reserved
06/13/2026 +3 days Advisory disclosed
06/13/2026 +0 days VulDB entry created
06/13/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-gp79-m99v-gjmh
Status: Confirmed

CVE: CVE-2026-53837 (🔒)
GCVE (CVE): GCVE-0-2026-53837
GCVE (VulDB): GCVE-100-370772

Entryinfo

Created: 06/13/2026 07:01
Changes: 06/13/2026 07:01 (76)
Complete: 🔍
Cache ID: 216::103

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