Craft CMS Improper Control of Generation of Code (Code Injection) Vulnerability - CVE-2026-31857 - Vulnerability Database

Craft CMS

Craft CMS Improper Control of Generation of Code (Code Injection) Vulnerability - CVE-2026-31857

High

Reference: CVE-2026-31857

NVD Link: https://nvd.nist.gov/vuln/detail/CVE-2026-31857

Title: Craft CMS Improper Control of Generation of Code (Code Injection) Vulnerability

Overview:

Craft is a content management system (CMS). Prior to 5.9.9 and 4.17.4 a Remote Code Execution vulnerability exists in the Craft CMS 5 conditions system. The BaseElementSelectConditionRule::getElementIds() method passes user-controlled string input through renderObjectTemplate() -- an unsandboxed Twig rendering function with escaping disabled. Any authenticated Control Panel user (including non-admin roles such as Author or Editor) can achieve full RCE by sending a crafted condition rule via standard element listing endpoints. This vulnerability requires no admin privileges no special permissions beyond basic control panel access and bypasses all production hardening settings (allowAdminChanges: false devMode: false enableTwigSandbox: true). Users should update to the patched 5.9.9 or 4.17.4 release to mitigate the issue.