CVE-2026-45334

Published Jul 16, 2026 CWE-862

Description

Kirby is an open-source content management system. In versions prior to 4.9.1 and 5.4.1, the content-locking feature returned lock information without checking the requesting user's access permissions. Kirby's Panel includes a content-locking feature that records which user currently has a model open for editing. This lock prevents conflicting edits by multiple users and displays the locking user's identity in the Panel UI so other users know who to contact. Internally, the locking user's email address and identifier are included in every Panel view payload and in error responses returned when a user attempts to edit a model that is currently locked by another user. This allowed a low-privilege authenticated Panel user, whose role was configured with users.access: false or users.list: false, to learn the email address and identifier of any user who currently had a model open for editing in the Panel, including administrators and other higher-privilege users. Content locks are active for a configurable window (10 minutes by default). The email address can allow admin account enumeration, target phishing, and feed credential-stuffing attacks against the Kirby installation or other sites. The internal user ID can be cross-referenced with other endpoints once the requester has obtained a higher privilege through unrelated means. This issue has been fixed in versions 4.9.1 and 5.4.1.

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Weakness Type (CWE)

CWE-862 Missing Authorization

References

Frequently Asked Questions

What is CVE-2026-45334? +
Kirby is an open-source content management system. In versions prior to 4.9.1 and 5.4.1, the content-locking feature returned lock information without checking the requesting user's access permissions. Kirby's Panel includes a content-locking feature that records which user currently has a model open for editing. This lock prevents conflicting edits by multiple users and displays the locking user's identity in the Panel UI so other users know who to contact. Internally, the locking user's email address and identifier are included in every Panel view payload and in error responses returned when a user attempts to edit a model that is currently locked by another user. This allowed a low-privilege authenticated Panel user, whose role was configured with users.access: false or users.list: false, to learn the email address and identifier of any user who currently had a model open for editing in the Panel, including administrators and other higher-privilege users. Content locks are active for a configurable window (10 minutes by default). The email address can allow admin account enumeration, target phishing, and feed credential-stuffing attacks against the Kirby installation or other sites. The internal user ID can be cross-referenced with other endpoints once the requester has obtained a higher privilege through unrelated means. This issue has been fixed in versions 4.9.1 and 5.4.1.
How do I check if I'm vulnerable to CVE-2026-45334? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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