CVE-2026-93848
Mattermost OpenID discovery endpoint request bypasses outbound connection filtering, allowing SSRF by a System Administrator
- Published
- Updated
- Reserved
- Assigned by
- Mattermost
Description
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
Timeline
ID reserved
By Mattermost
- 38 days later
· 38 days later
Published
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 | Low2.7 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N |
| NVDNVD · Analyzed | 3.1 | Low2.7 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.29% · top 78% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.7.
Weakness
Affected products
- affected 11.7.0 – ≤ 11.7.10
- unaffected 11.11.0
- unaffected 11.7.11
What to do
Solution: Update Mattermost to versions 11.11.0, 11.7.11 or higher.
References (1)
- MMSA-2026-00774 (opens in a new tab)vendor-advisory
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)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-93848)Record last updated .