CVE-2026-19600
Medium
Description
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763
SeverityMedium
CVSS4.5
Exploit probability—
Product
Mattermost Server
PublishedOct 16, 2026
First seenOct 16, 2026
Weakness typeCWE-532CWE-532
How to fix
Update
- mattermost mattermost_server11.7.10, 11.8.6, 11.9.2, 11.10.2 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_server | 11.7.0 ≤ v < 11.7.10, 11.8.0 ≤ v < 11.8.6, 11.9.0 ≤ v < 11.9.2, 11.10.0 ≤ v < 11.10.2 | 11.7.10, 11.8.6, 11.9.2, 11.10.2 |
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