Skip to main content

Mattermost CVE-2026-4054

| EUVD-2026-30590 MEDIUM
Improper Check for Unusual or Exceptional Conditions (CWE-754)
2026-05-15 Mattermost GHSA-j76w-p754-g2w7
Information Disclosure Mattermost
4.3
CVSS 3.1
Share

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

Lifecycle Timeline

1
Analysis Generated
May 15, 2026 - 19:38 vuln.today

DescriptionNVD

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

AnalysisAI

Client-side denial-of-service in Mattermost allows remote attackers to crash user browsers via maliciously crafted SVG files embedded in OpenGraph metadata or Markdown images. The vulnerability affects Mattermost Server versions 11.5.0-11.5.1, 10.11.0-10.11.13, and 11.4.0-11.4.3, where the server fails to validate proxied image response bodies. …

Sign in for full analysis, threat intelligence, and remediation guidance.

Full analysis requires sign-in

Get intelligence summaries, risk assessment, exploit details, threat intel, and remediation guidance.

Sign in - Free

Share

CVE-2026-4054 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy