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CVE-2026-19600

medium

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 ser…

Vendor / product: Mattermost — mattermost server

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

CVSS
4.9
4.9 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-10-16 08:17
Modified: 2026-10-27 20:58
NVD status: Analyzed
Last synced 19 hours ago
Verified against the source API 2026-10-28 11:30 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

mattermost / mattermost_server ≥11.7.0 <11.7.10, ≥11.8.0 <11.8.6, ≥11.9.0 <11.9.2, ≥11.10.0 <11.10.2

Weakness classification (CWE)

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://mattermost.com/security-updates

References

Data sources

NVD CVE API 2.0 — fetched 2026-10-28 11:30 UTC · record ↗

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