CVE-2026-21857: Redaxo has Path Traversal in Backup Addon Leading to Arbitrary File Read

CVE-2026-21857 · Severity: medium · CVSS 4 · Published 2026-01-05

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

Technologies: redaxo/source (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2026-21857 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-21857 being exploited in the wild.
How severe is CVE-2026-21857?
Medium severity, with a CVSS score of 4, published 5 January 2026.
Which products and versions are affected?
redaxo/source (Packagist) ECOSYSTEM:introduced=0,fixed=5.20.2.
Is there a fix for CVE-2026-21857?
Yes. redaxo/source (Packagist): upgrade to 5.20.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-21857?
Check whether you run redaxo/source (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • redaxo/source (Packagist): upgrade to 5.20.2 or later
    composer require redaxo/source:^5.20.2

Affected products

  • redaxo/source (Packagist) ECOSYSTEM:introduced=0,fixed=5.20.2

Identifiers

  • CVE-2026-21857
  • GHSA-824x-88xg-cwrv

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.