CVE-2026-93848lowCWE-918

CVE-2026-93848: low-severity vulnerability in Mattermost

Mattermost OpenID discovery endpoint request bypasses outbound connection filtering, allowing SSRF by a System Administrator

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 2.7epss 0.3%
Mattermost versions 11.7.x <= 11.7.10 fail to apply outbound internal-connection filtering to the OpenID discovery endpoint request which allows a System Administrator to determine whether internal addresses and ports are reachable from the server via an unauthenticated login request that triggers the discovery fetch.. Mattermost Advisory ID: MMSA-2026-00774
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N
Affected products
Mattermost · Mattermost
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