CVE-2026-115935
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.
How to fix
- craftcms cms5.11.2, 4.18.9 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| craftcms cms | 5.0.0 ≤ v < 5.11.2, 4.0.0 ≤ v < 4.18.9 | 5.11.2, 4.18.9 |
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