CVE-2026-3472 | Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 1… | CVSS 3.5 LOW

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

Metadata

CVE ID: CVE-2026-3472
State: PUBLISHED
Assigner: Mattermost
Reserved: 2026-03-03 11:25 UTC
Published: 2026-06-26 14:42 UTC
Last updated: 2026-06-26 15:41 UTC
Primary CWE: CWE-693
CWE-693: Protection Mechanism Failure
Vendor / Product: Mattermost / Mattermost
Sources: cve.org · NVD

Severity & Metrics

3.5 LOW CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
Mattermost	Mattermost	—	10.11.0 ≤ 10.11.18, 11.6.0 ≤ 11.6.3, 11.5.0 ≤ 11.5.6, 11.7.0 …

Weakness (CWE)

CWE	Source	Description
CWE-693	cna	CWE-693: Protection Mechanism Failure

CVSS scores (1)

Score	Severity	Version	Source	Vector
3.5	LOW	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N

References (1)

MMSA-2026-00619 https://mattermost.com/security-updates