- Description
- Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to properly validate user identity in the OpenID {{IsSameUser()}} comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user discovery flow.. Mattermost Advisory ID: MMSA-2026-00590
- Source
- responsibledisclosure@mattermost.com
- NVD status
- Analyzed
- Products
- mattermost_server
CVSS 3.1
- Type
- Primary
- Base score
- 6.1
- Impact score
- 5.2
- Exploitability score
- 0.9
- Vector string
- CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N
- Severity
- MEDIUM
- responsibledisclosure@mattermost.com
- CWE-303
- Hype score
- Not currently trending
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