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CVE-2026-53837 (GCVE-0-2026-53837)

Vulnerability from cvelistv5 – Published: 2026-06-12 21:57 – Updated: 2026-06-15 15:10 X_Open Source
VLAI
Title
OpenClaw < 2026.5.6 - Missing Channel Type Validation in Mattermost Event Handlers
Summary
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.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-15 15:09 UTC
CWE
  • CWE-636 - Not Failing Securely ('Failing Open')
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenClaw OpenClaw Affected: 0 , < 2026.5.6 (semver)
Unaffected: 2026.5.6 (semver)
    cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*
Create a notification for this product.
Date Public
2026-05-28 00:00
Credits
zsx (@zsxsoft) KeenSecurityLab qclawer
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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