DocumentationSeverity
Details
- CVSS score
- 8.7
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Overview
About vulnerability
Craft CMS allows any authenticated control panel user to submit an element-search condition whose element selector is evaluated as a sandboxed Twig object template. Craft’s allowed column filter delegates property lookup to Yii ArrayHelper, outside Twig’s SecurityPolicy. Repeated single-segment lookups therefore bypass the sandbox’s empty property/method allowlists.
The vulnerable condition value is ultimately cast to an integer. That does not protect the secret: the template can return author ID 1 when a guessed key character is correct and an impossible ID otherwise. The JSON endpoint returns entries for the first case and an empty array for the second, forming a stable remote character oracle.
After recovering GeneralConfig::securityKey, the same user can compute Craft’s generic HMAC wire format offline. Signed parameters such as redirect are then accepted and passed to unsandboxed View::renderObjectTemplate(), where Twig’s string-callable form can invoke native PHP callables. The regression proof uses the harmless substr() callback and observes abcdef becoming cdef; it does not execute an OS command.
Details
- Affected product:
- craftcms/cms , creocoder/yii2-nested-sets , verbb/feed-me , yii2tech/ar-softdelete , yiisoft/yii2 , yiisoft/yii2-debug , yiisoft/yii2-queue , yiisoft/yii2-swiftmailer
- Affected packages:
- cms @ 4.18.7 (+11 more)