CVE-2025-2571: Mattermost · Incorrect Implementation of Authentication Algorithm
Affects MattermostSource CVE Database V5
Not known to be exploited · CVSS 4.2 Medium.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 30 May 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Mattermost Mattermost | Affected
| Fixed in– |
AI-suggested
European organizations should prioritize upgrading Mattermost to versions beyond those affected once patches are released. In the interim, administrators should audit all bot accounts, especially those recently converted from user accounts, to verify their OAuth credential status and revoke any suspicious or stale tokens. Implement strict access controls and monitoring on account conversion processes to detect unauthorized or anomalous activity. Organizations should also review OAuth integration configurations to ensure that credential handling follows best practices, including token revocation and session management. Employing multi-factor authentication (MFA) for administrative actions related to account conversions can reduce risk. Additionally, monitoring logs for unusual OAuth signup flow activities and bot account behaviors can provide early detection of exploitation attempts. Since no patches are currently linked, engaging with Mattermost support or community forums for interim fixes or workarounds is advisable. Finally, educating administrators and users about the risks associated with OAuth credential handling and bot account management will strengthen overall security posture.
Description
Mattermost versions 10.7.x <= 10.7.0, 10.6.x <= 10.6.2, 10.5.x <= 10.5.3, 9.11.x <= 9.11.12 fail to clear Google OAuth credentials when converting user accounts to bot accounts, allowing attackers to gain unauthorized access to bot accounts via the Google OAuth signup flow.