CVE-2026-55791

Craft CMS is a content management system (CMS). Versions 4.0.0-RC1 and above, prior to 4.18.0 and 5.0.0-RC1, and above, prior to 5.10.0, are vulnerable to Server-Side Request Forgery (SSRF) and Arbitrary JavaScript Injection through the /actions/app/resource-js endpoint. By exploiting the default permissive trustedHosts configuration, an attacker can poison the Host or X-Forwarded-Host header to manipulate the application’s $baseUrl. This bypasses the endpoint’s internal URL validation, forcing the backend Guzzle client to fetch a malicious payload from an attacker-controlled server and reflect it to the client with a Content-Type: application/javascript header. The vulnerability manifests when assetManager.cacheSourcePaths is set to false. This issue has been fixed in versions 4.18.0 and 5.10.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/craftcms/cms/pull/18559
https://github.com/craftcms/cms/security/advisories/GHSA-c55v-343g-5xff

Configurations

No configuration.

History

02 Jul 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-02 00:16

Updated : 2026-07-02 16:16

NVD link : CVE-2026-55791

Mitre link : CVE-2026-55791

CVE.ORG link : CVE-2026-55791

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-644

Improper Neutralization of HTTP Headers for Scripting Syntax

CWE-918

Server-Side Request Forgery (SSRF)

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