CVE-2026-31857
CraftCMS has an RCE vulnerability via relational conditionals in the control panel
No known exploitation. EPSS puts it in the 57th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.9% chance of exploitation activity in the next 30 days, which ranks it in the 57th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 6 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Scored 8.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
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