CVE-2026-4853: The JetBackup – Backup, Restore & Migrate plugin for WordPress is vulnerable to Path Traversal leading to Arbitrary Directory Deletion in versions up ...

Description

The JetBackup – Backup, Restore & Migrate plugin for WordPress is vulnerable to Path Traversal leading to Arbitrary Directory Deletion in versions up to and including 3.1.19.8. This is due to insufficient input validation on the fileName parameter in the file upload handler. The plugin sanitizes the fileName parameter using sanitize_text_field(), which removes HTML tags but does not prevent path traversal sequences like '../'. The unsanitized filename is then directly concatenated in Upload::getFileLocation() without using basename() or validating the resolved path stays within the intended directory. When an invalid file is uploaded, the cleanup logic calls dirname() on the traversed path and passes it to Util::rm(), which recursively deletes the entire resolved directory. This makes it possible for authenticated attackers with administrator-level access to traverse outside the intended upload directory and trigger deletion of critical WordPress directories such as wp-content/plugins, effectively disabling all installed plugins and causing severe site disruption.

Metrics

CVSS 3.1

4.9/10

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.71%

49.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

References

Timeline

Published: Apr 17, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-4853?

The JetBackup – Backup, Restore & Migrate plugin for WordPress is vulnerable to Path Traversal leading to Arbitrary Directory Deletion in versions up to and including 3.1.19.8. This is due to insufficient input validation on the fileName parameter in the file upload handler. The plugin sanitizes the fileName parameter using sanitize_text_field(), which removes HTML tags but does not prevent path traversal sequences like '../'. The unsanitized filename is then directly concatenated in Upload::getFileLocation() without using basename() or validating the resolved path stays within the intended directory. When an invalid file is uploaded, the cleanup logic calls dirname() on the traversed path and passes it to Util::rm(), which recursively deletes the entire resolved directory. This makes it possible for authenticated attackers with administrator-level access to traverse outside the intended upload directory and trigger deletion of critical WordPress directories such as wp-content/plugins, effectively disabling all installed plugins and causing severe site disruption.

How severe is CVE-2026-4853?

CVE-2026-4853 has a CVSS score of 4.9/10 (MEDIUM severity). The EPSS model estimates a 0.71% probability of exploitation in the next 30 days.

How do I fix CVE-2026-4853?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.