CVE-2026-21857

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/redaxo/redaxo/releases/tag/5.20.2
https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv
https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv

Configurations

No configuration.

History

08 Jan 2026, 19:15

Type	Values Removed	Values Added
References	~~() https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv -~~	() https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv -

07 Jan 2026, 23:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-07 23:15

Updated : 2026-01-08 19:15

NVD link : CVE-2026-21857

Mitre link : CVE-2026-21857

CVE.ORG link : CVE-2026-21857

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CWE-24

Path Traversal: '../filedir'

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