CVE-2026-72782: cms 5.0.0-RC1 to before 5.10.6, 4.0.0-RC1 to before 4.18.2

Affected technology

cms · 5.0.0-RC1 to before 5.10.6
craftcms

cms · 4.0.0-RC1 to before 4.18.2
craftcms

Description’s affected range: versions >= 5.0.0-RC1 before 5.10.6 and >= 4.0.0-RC1 before 4.18.2 interpolate environment variables and secrets (via ${ENV_VAR} strings in the elementId parameter) into Twig templates before rendering

Component: Not specified by the source

Attack conditions (Vendor/CNA, CVSS 4.0): Network (remote) · Low privileges required · No user interaction required

What an attacker can do

An authenticated attacker with control panel access can render a malicious sandboxed Twig template and, using a blind error-based technique across many requests, incrementally leak arbitrary environment variables and secrets. Vendor/CNA’s CVSS 4.0 assessment (base score 7.1/10) rates confidentiality impact as high; integrity and availability impact as none.