VULNERABILITY INTELLIGENCE

CVE-2026-4054

CVSS score4.3 MEDIUM
EPSS probability0.24%
CISA KEVNot currently listed
Published2026-05-15
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to validate the response body of proxied images, which allows a remote attacker to enact client-side DoS via an SVG file served from an attacker-controlled origin under a non-SVG Content-Type header (e.g. image/png) embedded in an og:image meta tag or Markdown image link.. Mattermost Advisory ID: MMSA-2026-00630

Weakness classification

  • responsibledisclosure@mattermost.com: CWE-754

Primary references