Vulnerability · Published Oct 19, 2026 · Assigned by VulnCheck

CVE-2026-112777Craft CMS before 4.18.8 and 5.11.0 Twig create() Blocklist Bypass Leading to RCE

High 7.2

In plain English

A high-severity security flaw in cms from craftcms. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities).

Severity (CVSS 3.1)7.2High

Exploit odds (30 days)0.6%top 50.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Craft CMS 4.x before 4.18.8 and 5.x before 5.11.0 contains a blocklist bypass in the Twig create() function because its class-name checks are case-sensitive while PHP class resolution is not. Attackers with template-execution rights, such as Control Panel administrators, can instantiate SplFileObject via a lowercase class name to read .env secrets or write a PHP file into the webroot for remote code execution.

Affected products (as reported)

Vendor	Product	Versions
craftcms	cms	4.0.0 – before 4.18.8
craftcms	cms	5.0.0 – before 5.11.0

Weakness: CWE-184 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

References

GitHub Security Advisory (GHSA-w643-x88w-6wcm) vendor-advisory
VulnCheck Advisory: Craft CMS before 4.18.8 and 5.11.0 Twig create() Blocklist Bypass Leading to RCE third-party-advisory