CVE-2026-115938

Low privilege condition filter escapes Twig sandbox, recovers "securityKey" and reaches RCE

High 8.7

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.

Assigner
Hackrate

Published
2026-10-23

Updated
2026-10-23

Reserved
2026-10-23

Scores

Source	CVSS	Score	Severity	Vector
Hackrate	4.0	8.7	High	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
Hackrate	3.1	8.8	High	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses

CWE-1336

Affected

Vendor	Product	Versions
craftcms	cms	5.0.0 to < 5.11.2 (affected) 4.0.0 to < 4.18.9 (affected) others: unaffected

References

https://www.hckrt.com/hacktivity/HCKRT-DRNL9W third-party-advisorytechnical-descriptionmitigation
https://github.com/craftcms/cms/releases/tag/5.11.2 release-notes
https://github.com/craftcms/cms product
https://github.com/craftcms/cms/security/advisories/GHSA-v4q3-2g5g-wjj6 third-party-advisory

Full CVE JSON record (5.2)

API · GitHub · cve.org

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          "type": "reporter",
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          "lang": "en",
          "type": "coordinator",
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    "dateReserved": "2026-10-23T21:25:32.945Z",
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