---
id: CVE-2026-93848
title: >-
  Mattermost OpenID discovery endpoint request bypasses outbound connection
  filtering, allowing SSRF by a System Administrator
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 …
severity: low
cvss: 2.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-918
vendor: Mattermost
product: Mattermost
affected:
  - Mattermost >= 11.7.0 <= 11.7.10
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-26T15:34:04.498238Z'
published: '2026-10-26'
updated: '2026-10-26'
sourceUpdated: '2026-10-26T16:46:45.446Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-93848'
references:
  - url: 'https://mattermost.com/security-updates'
    label: MMSA-2026-00774
tags:
  - cve.org
ingestedAt: '2026-10-26T15:29:30.534Z'
---

## Overview

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

## Affected

- `Mattermost >= 11.7.0 <= 11.7.10`

## Remediation

Update Mattermost to versions 11.11.0, 11.7.11 or higher.