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CVE-2026-21857

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

Published: Jan 7, 2026Updated: Jan 20, 2026 Sources: CVE List NVD GHSACWE-22
6.5MEDIUM
NVD MITRE
EPSS Score
0.5%
Top 60.6%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available
Self-Check
Not available

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:HUI:NS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:HPrivileges Required
High
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-22CWE-24

Affected Products

redaxo
oss-projectaka cms, redaxo cms
redaxoOn-prem
Web & CMS Plugins / cms-core
Packagist
package-ecosystem
redaxo/source
OSS Libraries

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv
github.com
https://github.com/redaxo/redaxo/releases/tag/5.20.2
github.com
https://nvd.nist.gov/vuln/detail/CVE-2026-21857
nvd.nist.gov
and 1 more references View all →

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