Quick answers
- Is CVE-2026-56383 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-56383 being exploited in the wild.
- How severe is CVE-2026-56383?
- Medium severity, with a CVSS score of 4.8, published 21 June 2026.
- Which products and versions are affected?
- craftcms/cms (Packagist) ECOSYSTEM:introduced=4.5.0-beta.1,fixed=4.16.19.
- Is there a fix for CVE-2026-56383?
- Yes. craftcms/cms (Packagist): upgrade to 4.16.19 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-56383 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-56383?
- Check whether you run craftcms/cms (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- craftcms/cms (Packagist): upgrade to 4.16.19 or later
composer require craftcms/cms:^4.16.19
Technical details
A stored Cross-site Scripting (XSS) vulnerability exists in Craft CMS within the `editableTable.twig` component. The vulnerability is rooted in the lack of input sanitization for the 'Row Heading' column type in Table fields. An attacker with administrative privileges can inject a malicious payload (e.g., an `<img>` tag with an `onerror` attribute) into the default values of a table field. When another user views an object containing this field, the payload executes in their browser context. Exploitation requires the `allowAdminChanges` setting to be enabled, which is contrary to security best practices for production environments. The issue is patched in versions 4.16.19 and 5.8.23.
Affected products
- Pixel & Tonic Craft CMS >= 4.5.0-beta.1, <= 4.16.18; >= 5.0.0-RC1, <= 5.8.22
Identifiers
- CVE-2026-56383
- GHSA-6j87-m5qx-9fqp
Timeline
- 2026-02-23: patched: Fixes released in versions 4.16.19 and 5.8.23
- 2026-02-25: advisory: GitHub Advisory published