CVE-2026-31857

CraftCMS has an RCE vulnerability via relational conditionals in the control panel

HIGH 8.1EPSS 0.9%

Craft is a content management system (CMS). Prior to 5.9.9 and 4.17.4, a Remote Code Execution vulnerability exists in the Craft CMS 5 conditions system. The BaseElementSelectConditionRule::getElementIds() method passes user-controlled string input through renderObjectTemplate() -- an unsandboxed Twig rendering function with escaping disabled. Any authenticated Control Panel user (including non-admin roles such as Author or Editor) can achieve full RCE by sending a crafted condition rule via standard element listing endpoints. This vulnerability requires no admin privileges, no special permissions beyond basic control panel access, and bypasses all production hardening settings (allowAdminChanges: false, devMode: false, enableTwigSandbox: true). Users should update to the patched 5.9.9 or 4.17.4 release to mitigate the issue.

Affected: craftcms · cms
CVSS v4.0 GITHUB: 8.1 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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
CVSS v4.0 GitHub: 8.1 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U
CVSS v3.1 NVD: 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.92% chance of exploitation in the next 30 days, 60th percentile
Published: 2026-03-11
Updated: 2026-03-12

Proof-of-concept exploits (4)

0xTatsuki/CVE-2026-318570★ · 2026-10-01
0Asylum/CVE-2026-318571★ · 2026-09-30
TRX-0/CVE-2026-31857-craftcms-ssti0★ · 2026-09-21
kaizoku73/CVE-2026-31857-PoC0★ · 2026-10-08

CVE-2026-31857

Proof-of-concept exploits (4)

Security advisories

References

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