CVE-2026-93848 json
Mattermost OpenID discovery endpoint request bypasses outbound connection filtering, allowing SSRF by a System Administrator
published 2026-10-26 14 d ago modified 2026-11-02 6 d ago also EUVD-2026-109939
- cvss
- 2.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
Mattermost versions 11.7.x <= 11.7.10 fail to apply outbound internal-connection filtering to the OpenID discovery endpoint request which allows a System Administrator to determine whether internal addresses and ports are reachable from the server via an unauthenticated login request that triggers the discovery fetch.. Mattermost Advisory ID: MMSA-2026-00774
Patch / fix
- Mattermost Mattermost 11.7.11, 11.11.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 14 d ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 2.7 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N |
Affected products
- Mattermost Mattermost
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
mattermost.com
/security-updates
vendor-advisory
Sources
- CVE List CVE-2026-93848
- NVD CVE-2026-93848
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