Vulnerability in Craftcms Cms

CVE-2026-72778

Craft CMS versions from 4.0.0-RC1 before 4.18.2 and from 5.0.0-RC1 before 5.10.6 contain an authenticated remote code execution vulnerability in the control panel element-search condition handling. Craft cleanses the outer request-controlled condition array via Component::cleanseConfig(), but Conditions::createCondition() later decodes and merges the JSON string in condition.config without re-running cleanseConfig() on the decoded configuration. Because condition.config is a JSON string during the first cleanse, Yii special config keys such as 'as ...' and 'on ...' can be hidden inside it and, after JSON decoding, are interpreted by Yii as behavior/event configuration during FieldLayout object creation. An attacker with an authenticated control panel session (and a valid CSRF token) can exploit this to execute operating system commands as the PHP/web user.

Vulnerability class: Mass Assignment

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (54.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-72778: held from 0.004 to 0.008.

EPSS over last 30 days · oldest: 0.004 · newest: 0.008 · change: +0.004

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-72778?
CVE-2026-72778 is a high-severity vulnerability in Craftcms Cms, classified under Improperly Controlled Modification of Dynamically-Determined Object Attributes. CVSS score: 8.8/10. Published 2026-08-11.
How severe is CVE-2026-72778?
High severity. CVSS v3 base score is 8.8 out of 10.