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...

CVE-2026-55791 Craft CMS: Blind SSRF and Arbitrary JavaScript Injection via Host Header Poisoning in actionResourceJs

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...

CVE-2026-55791

Craft CMS vulnerability CVE-2026-55791 enables SSRF and Arbitrary JavaScript Injection via /actions/app/resource-js when assetManager.cacheSourcePaths is false and trustedHosts is permissive. An attacker can poison Host/X-Forwarded-Host to hijack $baseUrl, causing Craft::createGuzzleClient()->...