Is CVE-2026-56393 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-56393 being exploited in the wild.

How severe is CVE-2026-56393?

Medium severity, with a CVSS score of 4.8, published 21 June 2026.

Which products and versions are affected?

craftcms/cms (Packagist) ECOSYSTEM:introduced=5.0.0-RC1,fixed=5.9.0-beta.1.

Is there a fix for CVE-2026-56393?

Yes. craftcms/cms (Packagist): upgrade to 5.9.0-beta.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-56393 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-56393?

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.

CVE-2026-56393: Craft CMS stored XSS in settings names and field options

CVE-2026-56393 · Severity: medium · CVSS 4.8 · Published 2026-06-21

Craft CMS, a popular content management system, is vulnerable to a security flaw where malicious scripts can be saved in various administrative settings. If an attacker with administrative access saves a specially crafted name for a section, user group, or field, the script could execute in the browser of other administrators. This could lead to unauthorized actions being performed on behalf of other users or the theft of sensitive session information.

Technologies: craftcms/cms (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2026-56393 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-56393 being exploited in the wild.
How severe is CVE-2026-56393?: Medium severity, with a CVSS score of 4.8, published 21 June 2026.
Which products and versions are affected?: craftcms/cms (Packagist) ECOSYSTEM:introduced=5.0.0-RC1,fixed=5.9.0-beta.1.
Is there a fix for CVE-2026-56393?: Yes. craftcms/cms (Packagist): upgrade to 5.9.0-beta.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-56393 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-56393?: 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 5.9.0-beta.1 or later
```
composer require craftcms/cms:^5.9.0-beta.1
```

Technical details

Multiple stored Cross-Site Scripting (XSS) vulnerabilities exist in Craft CMS due to improper neutralization of input in the `_includes/forms/checkbox.twig` template, which uses the `|raw` filter on labels. An attacker with administrative privileges (and `allowAdminChanges` enabled) can inject malicious payloads into various sources including Section Names, Volume Names, User Group Names, Global Set Names, and Field Option Labels. These payloads are then executed when rendered in 'sinks' such as the Sources checklist in field settings or user permission pages. The vulnerability is addressed in versions 4.17.0-beta.1 and 5.9.0-beta.1.

Affected products

Pixel & Tonic Craft CMS >= 4.0.0-RC1, < 4.17.0-beta.1; >= 5.0.0-RC1, < 5.9.0-beta.1

Identifiers

CVE-2026-56393
GHSA-4mgv-366x-qxvx

Timeline

2026-03-02: disclosed
2026-03-03: advisory

References

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