CVE-2026-56393
CWE-79Published: June 21, 2026· Updated: Jun 22, 2026
Official Description
Craft CMS 4.x (>= 4.0.0-RC1, < 4.17.0-beta.1) and 5.x (>= 5.0.0-RC1, < 5.9.0-beta.1) contain multiple stored cross-site scripting vulnerabilities where settings names and field option labels are rendered without sanitization (e.g., via the checkbox.twig template, which used {{ label|raw }}). An authenticated administrator (with allowAdminChanges enabled) can inject malicious payloads into section names, volume names, user group names, global set names, generated field names, checkbox/radio option labels, and custom source labels, causing arbitrary JavaScript to execute in other users' control-panel sessions. Fixed in 4.17.0-beta.1 and 5.9.0-beta.1.
Technical Analysis
CVE-2026-56393 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (5)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-56393 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts