CVE-2026-115935

Control panel only API response emulation replaces "securityKey" and reaches server RCE

Published Oct 23, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Control panel only API response emulation replaces "securityKey" and reaches server RCE
First Time appeared Craftcms
Craftcms cms
Weaknesses CWE-94
CPEs cpe:2.3:a:craftcms:cms:*:*:*:*:*:*:*:*
Vendors & Products Craftcms
Craftcms cms
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Hackrate
Published
Updated
Nov 2, 2026, 2:45 PM
Reserved
Oct 23, 2026, 9:23 PM
Status
Awaiting Analysis
Published
Oct 23, 2026, 10:16 PM
Modified
Nov 2, 2026, 3:17 PM