CVE-2025-12419Account takeover on OAuth/OpenID-enabled servers
- 9.9CriticalCVSS base score
- 0.37%Exploitation in 30 daysEPSS · top 69% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validate OAuth state tokens during OpenID Connect authentication which allows an authenticated attacker with team creation privileges to take over a user account via manipulation of authentication data during the OAuth completion flow. This requires email verification to be disabled (default: disabled), OAuth/OpenID Connect to be enabled, and the attacker to control two users in the SSO system with one of them never having logged into Mattermost.
Timeline
ID reserved
By Mattermost
- 30 days later
· 30 days later
Published
- 3 months later
· 3 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| MattermostCNA (assigner) | 3.1 | Critical9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | Critical9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.37% · top 69% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.9.
Affected products
- affected 10.12.0 – ≤ 10.12.1
- affected 10.11.0 – ≤ 10.11.4
- affected 10.5.0 – ≤ 10.5.12
- affected 11.0.0 – ≤ 11.0.3
- unaffected 11.1.0
- unaffected 10.12.2
- unaffected 10.11.5
- unaffected 10.5.13
- unaffected 11.0.4
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/mattermost/mattermost-serverGHSA-3x39-62h4-f8j6 (opens in a new tab)
- Gogithub.com/mattermost/mattermost/server/v8GHSA-3x39-62h4-f8j6 (opens in a new tab)
What to do
Solution: Update Mattermost to versions 11.1.0, 10.12.2, 10.11.5, 10.5.13, 11.0.4 or higher.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-199827 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-3x39-62h4-f8j6 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-12419)Record last updated .