CVE-2026-9699 - Vulnerability Details - OpenCVE

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

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required High

Scope Changed

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

No data.

References

Link	Providers
https://mattermost.com/security-updates

History

Fri, 26 Jun 2026 16:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Fri, 26 Jun 2026 15:15:00 +0000

Type	Values Removed	Values Added
Description		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
Title		Mattermost Agents plugin logs unsanitized OpenAI API keys on authentication errors
Weaknesses		CWE-532
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-06-26T14:43:51.702Z

Updated: 2026-06-26T15:40:52.251Z

Reserved: 2026-05-27T12:08:53.502Z

Link: CVE-2026-9699

Vulnrichment

Updated: 2026-06-26T15:40:48.396Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

No data.

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