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
CVSS Details
- CVSS 3.1 Base Score: 6.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)
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