CVE-2026-21857
Description
REDAXO is a PHP-based content management system. Prior to version 5.20.2, authenticated users with backup permissions can read arbitrary files within the webroot via path traversal in the Backup addon's file export functionality. The Backup addon does not validate the `EXPDIR` POST parameter against the UI-generated allowlist of permitted directories. An attacker can supply relative paths containing `../` sequences (or even absolute paths inside the document root) to include any readable file in the generated `.tar.gz` archive. Version 5.20.2 fixes this issue.
How to fix
- redaxo redaxo5.20.2 or later
- redaxo/source5.20.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| redaxo redaxo | v < 5.20.2 | 5.20.2 |
| redaxo/sourcePackagist | v < 5.20.2 | 5.20.2 |
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Attack Surface Management
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