CVE-2026-21857 (GCVE-0-2026-21857)

Vulnerability from cvelistv5 – Published: 2026-01-07 22:32 – Updated: 2026-01-08 18:17
VLAI?
Title
Redaxo has Path Traversal in Backup Addon Leading to Arbitrary File Read
Summary
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.
Severity ?
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
CWE
  • CWE-24 - Path Traversal: '../filedir'
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
References
Impacted products
Vendor Product Version
redaxo redaxo Affected: < 5.20.2
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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