CVE-2026-21857

Redaxo has Path Traversal in Backup Addon Leading to Arbitrary File Read

State: Published
Severity: 8.3 High
Published: Jan 7, 2026
Updated: Jan 8, 2026
Reserved: Jan 5, 2026

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.

Scores

CVSS	Score	Vector	Source
4.0	8.3 High	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:N	GitHub_M

Weaknesses

CWE-24 Path Traversal: '../filedir'
CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Affected Products

Product	Versions
redaxoredaxo	< 5.20.2Affected

References

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