CVE-2026-4273
Insufficient token rotation validation in remote cluster invite confirmation
CVSS Score
3.7
EPSS Score
0.0%
EPSS Percentile
0th
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate that the RefreshedToken differs from the original invite token during remote cluster invite confirmation which allows an authenticated attacker to bypass token rotation and reuse the original invite token via sending a crafted invite confirmation with a RefreshedToken matching the original token. Mattermost Advisory ID: MMSA-2026-00575
| CWE | CWE-863 |
| Vendor | mattermost |
| Product | mattermost |
| Published | May 18, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
Mattermost / Mattermost
11.5.0 ≤ 11.5.1 10.11.0 ≤ 10.11.13
Credits
daw10