PT-2026-33054 · Mattermost · Mattermost

Published

2026-04-15

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Updated

2026-04-15

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CVE-2026-3590

CVSS v3.1

6.5

Medium

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to enforce atomic single-use consumption of guest magic link tokens, which allows an attacker with access to a valid magic link to establish multiple independent authenticated sessions via concurrent requests.. Mattermost Advisory ID: MMSA-2026-00624

Fix

Time Of Check To Time Of Use

Weakness Enumeration

Related Identifiers

CVE-2026-3590

Affected Products

Mattermost