Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

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

Quick assessment

Affected
craftcms cms
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

CraftCMS cms是CraftCMS的内容管理系统。 Craft CMS 4.0.0-RC1版本至4.18.0之前版本和5.0.0-RC1版本至5.10.0之前版本存在安全漏洞，该漏洞源于通过/actions/app/resource-js端点利用默认宽松的trustedHosts配置，攻击者可操纵Host或X-Forwarded-Host标头篡改应用程序的$baseUrl，绕过端点内部URL验证，导致服务端请求伪造和任意JavaScript注入。

AI Predicted 8.5 Difficulty: Easy EPSS 0.46% · P38

Affected Version Matrix 2

VendorProduct Version RangeStatus
craftcms cms >= 5.0.0-RC1, < 5.10.0 affected
>= 4.0.0-RC1, < 4.18.0 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-55791

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Craft CMS: Blind SSRF and Arbitrary JavaScript Injection via Host Header Poisoning in actionResourceJs
Source: CVE Program / CVE List V5
Vulnerability Description
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 $baseUrl. This bypasses the endpoint’s internal URL validation, forcing the backend Guzzle client to fetch a malicious payload from an attacker-controlled server and reflect it to the client with a Content-Type: application/javascript header. The vulnerability manifests when assetManager.cacheSourcePaths is set to false. This issue has been fixed in versions 4.18.0 and 5.10.0.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Source: CVE Program / CVE List V5
Vulnerability Type
服务端请求伪造(SSRF)
Source: CVE Program / CVE List V5
Vulnerability Title
Craft CMS 跨站脚本漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
CraftCMS cms是CraftCMS的内容管理系统。 Craft CMS 4.0.0-RC1版本至4.18.0之前版本和5.0.0-RC1版本至5.10.0之前版本存在安全漏洞，该漏洞源于通过/actions/app/resource-js端点利用默认宽松的trustedHosts配置，攻击者可操纵Host或X-Forwarded-Host标头篡改应用程序的$baseUrl，绕过端点内部URL验证，导致服务端请求伪造和任意JavaScript注入。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
craftcms cms >= 5.0.0-RC1, < 5.10.0 -

II. Public POCs for CVE-2026-55791

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-55791

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-55791 (1)

Vendor Advisories for CVE-2026-55791 (1)

Same Patch Batch · craftcms · 2026-07-01 · 9 CVEs total

CVE-2026-50284 Craft CMS: Missing peer-permission check in `AssetsController::actionDeleteFolder` allows
CVE-2026-50280 Craft CMS: Authorization bypass in `entries/move-to-section` via missing target-section sa
CVE-2026-50279 Craft CMS: Authorship spoofing in `entries/save-entry` via pre-check/post-mutation authori
CVE-2026-50283 Craft CMS: Unauthorized Deletion of Source Assets During File Replacement
CVE-2026-55793 Craft CMS: Stored XSS via Structure entry title in table view
CVE-2026-55790 Craft CMS: DOM XSS via GitHub issue title in CraftSupport widget
CVE-2026-55792 Craft CMS: Sensitive File Disclosure / Server-Side File Read
CVE-2026-55794 Craft CMS: Potential authenticated Remote Code Execution via referrer redirect

IV. Related Vulnerabilities

Same product: cms
Same vendor: craftcms
Same weakness: CWE-918

V. Comments for CVE-2026-55791

No comments yet

Leave a comment