CVE-2026-28782: Craft has a Permission Bypass and IDOR in Duplicate Entry Action

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-04 · updated 2026-06-17
Weakness: CWE-639

Description

Craft is a content management system (CMS). Prior to 5.9.0-beta.1 and 4.17.0-beta.1, the "Duplicate" entry action does not properly verify if the user has permission to perform this action on the specific target elements. Even with only "View Entries" permission (where the "Duplicate" action is restricted in the UI), a user can bypass this restriction by sending a direct request. Furthermore, this vulnerability allows duplicating other users' entries by specifying their Entry IDs. Since Entry IDs are incremental, an attacker can trivially brute-force these IDs to duplicate and access restricted content across the system. This vulnerability is fixed in 5.9.0-beta.1 and 4.17.0-beta.1.

Affected products

craftcms cms: from 4.0.0 (excl.) before 4.17.0; from 5.0.0 (excl.) before 5.9.0; 4.0.0, 4.0.0-rc1, 4.0.0-rc2, 4.0.0-rc3, 5.0.0, 5.0.0-rc1 — fixed in 4.17.0, 5.9.0

How to fix

Upgrade to a fixed version: craftcms cms 4.17.0, 5.9.0. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-28782 or the next vulnerability affects your stack