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

Vulnerability from cvelistv5 – Published: 2026-06-12 21:57 – Updated: 2026-06-12 21:57 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
CWE
  • CWE-636 - Not Failing Securely ('Failing Open')
Assigner
References
Impacted products
Vendor Product Version
OpenClaw OpenClaw Affected: 0 , < 2026.5.6 (semver)
Unaffected: 2026.5.6 (semver)
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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}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.