What’s Vulnerable › Vulnerabilities

CVE-2026-18386: WP BackItUp Community Edition <= 2.1.0 - Authenticated (Administrator+) Path Traversal to Arbitrary File Read via 'backup_file' Parameter

• Severity: medium (CVSS 4.9 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-10 · updated 2026-09-10
• Weakness: CWE-22

Description

The WP BackItUp Community Edition plugin for WordPress is vulnerable to Directory Traversal in all versions up to, and including, 2.1.0 via the 'backup_file' parameter parameter. This makes it possible for authenticated attackers, with administrator-level access and above, to read the contents of arbitrary files on the server, which can contain sensitive information. The basename() normalization present in the handler only executes when the traversed target path does not exist, providing no protection against reads of existing files.

Affected products

• cssimmon WP BackItUp Community Edition: through 2.1.0

References

• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.0.0/lib/includes/class-wpbackitup-admin.php#L1391
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.0.0/lib/includes/handler_download.php#L30
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.0.0/lib/includes/handler_download.php#L73
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.0.0/lib/includes/handler_download.php#L77
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.1.0/lib/includes/class-wpbackitup-admin.php#L1391
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.1.0/lib/includes/handler_download.php#L30
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.1.0/lib/includes/handler_download.php#L73
• https://plugins.trac.wordpress.org/browser/wp-backitup/tags/2.1.0/lib/includes/handler_download.php#L77
• https://www.wordfence.com/threat-intel/vulnerabilities/id/50272c8a-2e23-490d-8865-68ae49228895?source=cve

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