Unauthenticated Craft CMS users can trigger a database backup
Published 5 Jan 2026 · Updated 3 Feb 2026
Affected packages
- Affected
- >=5.0.0-RC1 <5.8.21
- Fixed in
- 5.8.21
composer require craftcms/cms:^5.8.21- Affected
- >=3.0.0 <4.16.17
- Fixed in
- 4.16.17
composer require craftcms/cms:^4.16.17Details
Unauthenticated users can trigger database backup operations the updater/backup action, potentially leading to resource exhaustion or information disclosure.
Users should update to the patched versions (5.8.21 and 4.16.17) to mitigate the issue.
Craft 3 users should update to the latest Craft 4 and 5 releases, which include the fixes.
References:
https://github.com/craftcms/cms/commit/f83d4e0c6b906743206b4747db4abf8164b8da39
https://github.com/craftcms/cms/blob/5.x/CHANGELOG.md#5821---2025-12-04
Affected Endpoints
POST /admin/actions/updater/backup(unauthenticated)
Vulnerability Details
Root Cause
All updater/* actions are explicitly configured with anonymous access:
// BaseUpdaterController.php protected array|bool|int $allowAnonymous = self::ALLOW_ANONYMOUS_LIVE | self::ALLOW_ANONYMOUS_OFFLINE;
Attack Vector
1. Send unauthenticated POST request to /admin/actions/updater/backup
2. Database backup executes with configured backupCommand
Is GHSA-v64r-7wg9-23pr in any of your client repos?
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References
Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.