CVE-2026-115935

The app/process-api-response-headers action accepts fake Craft API response headers from any authenticated control panel user. A non-admin user with only accessCp can place newline characters in X-Craft-Plugin-Licenses. Craft passes this value to its .env writer without removing the newlines. This lets the user insert a new attacker-known CRAFT_SECURITY_KEY into .env. After Craft loads that key, the user can forge a signed login redirect containing a Twig system() callback. This is different from the previous report. That report reads the existing key through a Twig sandbox bypass. This report replaces the key through fake API headers and CRLF injection. Fixing either source does not fix the other.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/craftcms/cms
https://github.com/craftcms/cms/releases/tag/5.11.2
https://github.com/craftcms/cms/security/advisories/GHSA-9hp6-3565-gvh5
https://www.hckrt.com/hacktivity/HCKRT-WM3VSE

Configurations

No configuration.

History

23 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-23 22:16

Updated : 2026-10-26 18:39

NVD link : CVE-2026-115935

Mitre link : CVE-2026-115935

CVE.ORG link : CVE-2026-115935

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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