CVE-2026-112770 craftcms CVE debrief

Who should care

Defenders responsible for Craft CMS installations, particularly those with control panel user accounts, should assess exposure and prioritize patching. This includes reviewing compensating controls for exposed systems, monitoring for suspicious activity, and verifying affected systems. Security teams should track exceptions, retest remediated assets, and close the item only after evidence is documented.

Why it matters

CVE-2026-112770 is a high-severity remote code execution vulnerability in Craft CMS, affecting versions before 4.18.8 and 5.11.0. Authenticated control panel users can exploit the vulnerability to execute arbitrary code as the web user. Defenders should prioritize patching and verifying affected systems.

• Potential code execution as the web user
• Possible webshell creation in the webroot
• Risk of arbitrary code execution via element-select condition rules
• Need for verification of affected versions and patch application

Technical summary

The vulnerability is caused by the Twig group filter invoking non-string arrow arguments as callables without the checkArrow guard. This allows authenticated control panel users to pass an array-callable, such as FileHelper::writeToFile, via element-select condition rules to write a webshell to the webroot and execute code as the web user. The vulnerability affects Craft CMS versions before 4.18.8 and 5.11.0, and has a high CVSS score of 8.7. Defenders should prioritize patching and verifying affected systems, and monitor for suspicious activity on control panel user accounts.

Defensive priority

High priority for patching and verifying affected systems

Recommended defensive actions

• Patch Craft CMS to version 4.18.8 or 5.11.0
• Verify affected systems and apply patches
• Monitor for suspicious activity on control panel user accounts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on the vulnerability, affected versions, and references to vendor advisories. The vulnerability has a high CVSS score of 8.7 and is considered a high-severity issue. There are references to vendor advisories and third-party advisories that provide additional information on the vulnerability. Defenders should verify affected systems and apply patches, and monitor for suspicious activity on control panel user accounts.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.