Craft CMS stores arbitrary content provided by unauthenticated users in session files. This content could be accessed and executed, possibly using an independent vulnerability. Craft CMS redirects requests that require authentication to the login page and generates a session file on the server at '/var/lib/php/sessions'. Such session files are named 'sess_[session_value]', where '[session_value]' is provided to the client in a 'Set-Cookie' response header. Craft CMS stores the return URL requested by the client without sanitizing parameters. Consequently, an unauthenticated client can introduce arbitrary values, such as PHP code, to a known local file location on the server. Craft CMS versions 5.7.5 and 4.15.3 have been released to address this issue.

Craft is a flexible, user-friendly CMS for creating custom digital experiences on the web and beyond. Starting from version 3.0.0-RC1 to before 3.9.15, 4.0.0-RC1 to before 4.14.15, and 5.0.0-RC1 to before 5.6.17, Craft is vulnerable to remote code execution. This is a high-impact, low-complexity attack vector. This issue has been patched in versions 3.9.15, 4.14.15, and 5.6.17, and is an additional fix for CVE-2023-41892.

Craft is a flexible, user-friendly CMS for creating custom digital experiences on the web and beyond. This is an remote code execution (RCE) vulnerability that affects Craft 4 and 5 installs where your security key has already been compromised. Anyone running an unpatched version of Craft with a compromised security key is affected. This vulnerability has been patched in Craft 5.5.8 and 4.13.8. Users who cannot update to a patched version, should rotate their security keys and ensure their privacy to help migitgate the issue.