CVE-2026-3590
Race Condition in Guest Magic Link Authentication Allows Token Reuse
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
7th
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
| CWE | CWE-367 |
| Vendor | mattermost |
| Product | mattermost |
| Published | Apr 15, 2026 |
| Last Updated | Apr 15, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
Mattermost / Mattermost
10.11.0 ≤ 10.11.12 11.5.0 ≤ 11.5.0 11.4.0 ≤ 11.4.2 11.3.0 ≤ 11.3.2
Credits
Edgar Bellot Micó