CVE-2026-3472
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
SeverityLow
CVSS3.5
Exploit probability—
Product
Mattermost Server
PublishedJun 26, 2026
First seenJun 26, 2026
Weakness typeCWE-693CWE-693
How to fix
Update
- mattermost mattermost_server10.11.19, 11.5.7, 11.6.4 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_server | 10.11.0 ≤ v < 10.11.19, 11.5.0 ≤ v < 11.5.7, 11.6.0 ≤ v < 11.6.4 | 10.11.19, 11.5.7, 11.6.4 |
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