CVE-2026-50279: CWE-285: Improper Authorization in craftcms cms
Craft CMS versions from 5.0.0-RC1 up to but not including 5.9.21 contain an improper authorization vulnerability in the EntriesController::actionSaveEntry() method. This flaw allows a low-privileged user who is an existing author of an entry to reassign the entry's authorship to another user without having the required peer-author-change permission. The issue arises because authorization checks are performed before the author list is mutated, and no re-authorization occurs after the change. This vulnerability has been fixed in version 5.9.21.
AI Analysis
Technical Summary
In Craft CMS versions 5.0.0-RC1 through 5.9.20, the EntriesController::actionSaveEntry() method performs permission checks for editing entries before applying changes to the authorship model. Because the controller accepts attacker-supplied author parameters and does not re-run authorization after modifying the author list, a user who is already an author on an entry can spoof authorship by reassigning the entry to another user without holding the dedicated peer-author-change permission. This improper authorization vulnerability (CWE-285) allows unauthorized modification of entry authorship. The issue is resolved in version 5.9.21.
Potential Impact
An attacker with low privileges who is an existing author of an entry can reassign the entry's authorship to another user without proper authorization. This could lead to unauthorized content ownership changes, potentially impacting content integrity and accountability within the CMS. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
This vulnerability has been fixed in Craft CMS version 5.9.21. Users should upgrade to version 5.9.21 or later to remediate this issue. Patch status is not explicitly confirmed in the vendor advisory, but the fix version is clearly stated. No additional mitigations are specified.
CVE-2026-50279: CWE-285: Improper Authorization in craftcms cms
Description
Craft CMS versions from 5.0.0-RC1 up to but not including 5.9.21 contain an improper authorization vulnerability in the EntriesController::actionSaveEntry() method. This flaw allows a low-privileged user who is an existing author of an entry to reassign the entry's authorship to another user without having the required peer-author-change permission. The issue arises because authorization checks are performed before the author list is mutated, and no re-authorization occurs after the change. This vulnerability has been fixed in version 5.9.21.
CVSS v4.0
Score 7.6high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
In Craft CMS versions 5.0.0-RC1 through 5.9.20, the EntriesController::actionSaveEntry() method performs permission checks for editing entries before applying changes to the authorship model. Because the controller accepts attacker-supplied author parameters and does not re-run authorization after modifying the author list, a user who is already an author on an entry can spoof authorship by reassigning the entry to another user without holding the dedicated peer-author-change permission. This improper authorization vulnerability (CWE-285) allows unauthorized modification of entry authorship. The issue is resolved in version 5.9.21.
Potential Impact
An attacker with low privileges who is an existing author of an entry can reassign the entry's authorship to another user without proper authorization. This could lead to unauthorized content ownership changes, potentially impacting content integrity and accountability within the CMS. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
This vulnerability has been fixed in Craft CMS version 5.9.21. Users should upgrade to version 5.9.21 or later to remediate this issue. Patch status is not explicitly confirmed in the vendor advisory, but the fix version is clearly stated. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-04T16:26:05.985Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a45a80827e9c797195b4138
Added to database: 07/01/2026, 23:51:36 UTC
Last enriched: 07/02/2026, 00:06:28 UTC
Last updated: 07/02/2026, 00:31:51 UTC
Views: 5
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