CVE-2026-3472 (GCVE-0-2026-3472)

Vulnerability from cvelistv5 – Published: 2026-06-26 14:42 – Updated: 2026-06-26 15:41
VLAI
Title
Markdown image rendering bypass in AI bot tool result posts in Mattermost
Summary
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
Severity
3.5 (Low)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-26 15:41 UTC
CWE
  • CWE-693 - Protection Mechanism Failure
Assigner
Mattermost CNA under the mitre root
CNA scorecard B 80/100 over 107 records in the last 180 days details
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 10.11.0 , ≤ 10.11.18 (semver)
Affected: 11.6.0 , ≤ 11.6.3 (semver)
Affected: 11.5.0 , ≤ 11.5.6 (semver)
Unaffected: 11.7.0
Unaffected: 10.11.19
Unaffected: 11.6.4
Unaffected: 11.5.7
guessed Create a notification for this product.
Credits
Juho Forsén
Show details on NVD website
To clipboard 

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