CVE-2026-3472 - Vulnerability Details - OpenCVE

Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to properly apply markdown image rendering restrictions to AI bot tool result posts, which allows an authenticated attacker to exfiltrate data to an attacker-controlled server via injecting markdown image syntax into tool result content rendered by a victim's client.. Mattermost Advisory ID: MMSA-2026-00619

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products

References

Link	Providers
https://mattermost.com/security-updates

History

Fri, 26 Jun 2026 16:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Fri, 26 Jun 2026 15:15:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to properly apply markdown image rendering restrictions to AI bot tool result posts, which allows an authenticated attacker to exfiltrate data to an attacker-controlled server via injecting markdown image syntax into tool result content rendered by a victim's client.. Mattermost Advisory ID: MMSA-2026-00619
Title		Markdown image rendering bypass in AI bot tool result posts in Mattermost
Weaknesses		CWE-693
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 3.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-06-26T14:42:24.154Z

Updated: 2026-06-26T15:41:09.780Z

Reserved: 2026-03-03T11:25:53.785Z

Link: CVE-2026-3472

Vulnrichment

Updated: 2026-06-26T15:41:06.401Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-06-26T16:30:03Z

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