CVE-2026-4853 json
JetBackup <= 3.1.19.8 - Authenticated (Administrator+) Arbitrary Directory Deletion via Path Traversal in 'fileName' Parameter
published 2026-04-17 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-23354
- cvss
- 4.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.71% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.9 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N |
Affected products
- backupguard JetBackup – Backup, Restore & Migrate
Classification
- Weakness
-
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/4aa0fa80-05dd-4fe1-b7b5-7ed0cf13053c?source=cve
- plugins.trac.wordpress.org /browser/backup/trunk/src/JetBackup/Upload/Upload.php#L66
- plugins.trac.wordpress.org /browser/backup/tags/3.1.17.5/src/JetBackup/Upload/Upload.php#L66
- plugins.trac.wordpress.org /browser/backup/trunk/src/JetBackup/Ajax/Calls/AddToQueue.php#L64
- plugins.trac.wordpress.org /browser/backup/tags/3.1.17.5/src/JetBackup/Ajax/Calls/AddToQueue.php#L64
- plugins.trac.wordpress.org /browser/backup/trunk/src/JetBackup/Ajax/Calls/AddToQueue.php#L244
- plugins.trac.wordpress.org /browser/backup/tags/3.1.17.5/src/JetBackup/Ajax/Calls/AddToQueue.php#L244
- plugins.trac.wordpress.org /changeset?sfp_email=&sfph_mail=&reponame=&old=3495633%40backup&new=3495633%40backup&sfp_email=&sfph_mail=
Sources
- CVE List CVE-2026-4853
- NVD CVE-2026-4853
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.