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
Metrics
Affected Vendors & Products
References
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| https://mattermost.com/security-updates |
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History
Fri, 15 May 2026 21:15:00 +0000
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ssvc
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Fri, 15 May 2026 20:45:00 +0000
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Mattermost
Mattermost mattermost |
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| Vendors & Products |
Mattermost
Mattermost mattermost |
Fri, 15 May 2026 19:00:00 +0000
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| 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 | |
| Title | SVG content served through Mattermost image proxy despite Content-Type restrictions causes client-side denial of service | |
| Weaknesses | CWE-754 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: Mattermost
Published:
Updated: 2026-05-15T20:23:24.121Z
Reserved: 2026-03-12T16:08:33.686Z
Link: CVE-2026-4054
Updated: 2026-05-15T20:23:20.560Z
Status : Received
Published: 2026-05-15T19:17:04.803
Modified: 2026-05-15T19:17:04.803
Link: CVE-2026-4054
No data.
OpenCVE Enrichment
Updated: 2026-05-15T21:00:09Z