SVG content served through Mattermost image proxy despite Content-Type restrictions causes client-side denial of service
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
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| Mattermost | Mattermost | unaffected |
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Configuration 1 [-]
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No data.
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| Mattermost | Mattermost |
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Vendor Solution
Update Mattermost to versions 11.6.0, 11.5.2, 10.11.14, 11.4.4 or higher.
| Source | ID | Title |
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Github GHSA |
GHSA-j76w-p754-g2w7 | Mattermost doesn't validate the response body of proxied images |
No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.242% probability within 30 days)
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| https://mattermost.com/security-updates |
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Mattermost mattermost Server
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| CPEs | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | |
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Mattermost mattermost Server
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| Metrics |
ssvc
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| First Time appeared |
Mattermost
Mattermost mattermost |
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| Vendors & Products |
Mattermost
Mattermost mattermost |
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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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