CVE-2026-86730

Craft CMS versions before 5.10.12 fail to properly cleanse string-typed field-layout elements, allowing authenticated control-panel users to inject Yii2 behavior attachments and event handlers. Attackers can post field-layout tab elements as JSON strings to bypass cleanse validation, then trigger arbitrary object instantiation and code execution through Craft::createObject().

  • Published Sep 8, 2026
  • CVSS 8.7 high
  • 0.7% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-86730 at the National Vulnerability Database