Backup - Arbitrary File Upload (CVE-2026-4853)
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.
CVE-2026-4853
MEDIUM
CVSS 4.9
Published 2026-04-17
Updated 2026-06-17
AI Risk Moderate (51/100)
Active Exploit: No strong signal
Published Exploit: No public exploit references
Priority: P4 Planned
Severity Band
MEDIUM
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Affected Components
2
Reference Links
8
AI Risk Engine
Moderate (51/100)
Exploitability
High
Active Exploitation
No strong signal
Published Exploit Status
No public exploit references
AI Context
Machine-generated threat intelligence
AI
Updated 199 days ago
AI enriched 199 days ago (2026-04-18 00:19 UTC)
Technical 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…
Potential Impact
Severity is MEDIUM (CVSS 4.9). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.
Exploitability Assessment
Exploitability is assessed as High based on remote code execution potential.
Primary risk drivers: remote code execution potential
Mitigation Recommendations
Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.
Detection & Monitoring
Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.
Business Impact Lens
AI risk score 51/100 (Moderate, High) with priority P4 Planned. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.
