CVE-2026-9699
Medium
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
SeverityMedium
CVSS6.8
Exploit probability—
Product
Mattermost
PublishedJun 26, 2026
First seenJun 26, 2026
Weakness typeCWE-532CWE-532
How to fix
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Mattermost Mattermost | v ≤ 10.18.11, v ≤ 11.3.6, v ≤ 11.6.5 | — |
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