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VULNERABILITIES

CVE-2026-96259 Details

Description

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to apply the internal-connection filter to OAuth endpoint requests, which allows a System Administrator to make the server issue requests to internal network addresses and read the responses via the configured OAuth token and userinfo endpoints.. Mattermost Advisory ID: MMSA-2026-00776

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:5.5 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://mattermost.com/security-updates [email protected]

Weakness Enumeration

CWE-IDCWE NameSource
CWE-918Server-Side Request Forgery (SSRF)[email protected]

Affected Products

No affected product data is available for this CVE.

Change History

2 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-96259
NVD Published Date:
Sep 22, 2026
NVD Last Modified:
Sep 23, 2026
Source:
[email protected]
CVE-2026-96259 Details - Not Deferred