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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

cpe:2.3:a:redaxo:redaxo:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-07 23:15

Updated : 2026-01-20 18:49

NVD link : CVE-2026-21857

Mitre link : CVE-2026-21857

CVE.ORG link : CVE-2026-21857

JSON object : View

Products Affected

redaxo

redaxo

CWE

CWE-22

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

CWE-24

Path Traversal: '../filedir'

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