CVE-2026-21857

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

CVSS 8.3 HIGHEPSS 0.5%CWE-22 CWE-24

Vexday Risk Score

21Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 8.3EPSS 0.5%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

07 Jan 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

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:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:N

Affected products

redaxo · redaxo

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References

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