CVE-2026-9699 (GCVE-0-2026-9699)

Vulnerability from cvelistv5 – Published: 2026-06-26 14:43 – Updated: 2026-06-26 15:40
VLAI
Title
Mattermost Agents plugin logs unsanitized OpenAI API keys on authentication errors
Summary
Mattermost Plugins versions <=11.6 10.18.11 11.3.6 11.6.5.0 fail to sanitize error responses from the OpenAI API before logging, which allows a user with access to server logs or support packets to obtain a valid or partially reconstructable OpenAI API key via inspection of mattermost.log entries generated during authentication failures. Mattermost Advisory ID: MMSA-2026-00609
Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-532 - Insertion of Sensitive Information into Log Files
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 0 , ≤ 10.18.11 (semver)
Affected: 0 , ≤ 11.3.6 (semver)
Affected: 0 , ≤ 11.6.5 (semver)
Unaffected: 11.7.0
Unaffected: 10.11.19
Unaffected: 11.6.4
Unaffected: 11.5.7
Create a notification for this product.
Credits
Edgar Bellot Micó
Show details on NVD website
To clipboard 

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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

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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.