CVE-2026-109305: Improper Neutralization of Special Elements Used in a Template Engine in craftcms cms
Description
Craft CMS versions from 5.10.2 up to but not including 5.10.14 contain a vulnerability in the Twig template engine sandbox. This flaw allows non-admin users with the System Messages permission to bypass sandbox restrictions and invoke PHP callables, potentially executing arbitrary code as the web user. The vulnerability arises from improper neutralization of special elements used in templates, specifically via the "has some" and "has every" operators. The CVSS 4.0 score is 8.7, indicating a high severity issue.
CVSS v4.0
Score 8.7high
Affected software
craftcms
cms
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-109305 is a sandbox bypass vulnerability in Craft CMS's Twig template engine affecting versions >=5.10.2 and <5.10.14. It allows users with limited privileges (System Messages permission) to execute arbitrary PHP callables such as passthru or system by exploiting the "has some" and "has every" operators in sandboxed templates. This improper neutralization of special elements enables code execution as the web user, bypassing intended sandbox restrictions.
Potential Impact
An attacker with the System Messages permission can execute arbitrary PHP code on the server with the privileges of the web user. This can lead to unauthorized command execution, data exposure, or further compromise of the hosting environment. The vulnerability does not require admin privileges but does require the System Messages permission, which may be granted to non-admin users.
Mitigation Recommendations
A fix is available in Craft CMS version 5.10.14. Users should upgrade to 5.10.14 or later to remediate this vulnerability. Until patched, restrict the System Messages permission to trusted users only. Patch status is confirmed by the affected version range indicating the fix in 5.10.14.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-10-12T14:13:39.027Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6acd0c112cdf04f656b11be6
Added to database: 10/12/2026, 16:34:25 UTC
Last enriched: 10/12/2026, 17:19:09 UTC
Last updated: 10/12/2026, 21:46:49 UTC
Views: 9
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