CVE-2026-18386 json
WP BackItUp Community Edition <= 2.1.0 - Authenticated (Administrator+) Path Traversal to Arbitrary File Read via 'backup_file' Parameter
published last mo. modified last mo. also EUVD-2026-75237
- cvss
- 4.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 66%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
1.11% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-09).
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
- cssimmon WP BackItUp Community Edition
Classification
- Weakness
-
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/50272c8a-2e23-490d-8865-68ae49228895?source=cve
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.1.0/lib/includes/handler_download.php#L77
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.1.0/lib/includes/handler_download.php#L73
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.1.0/lib/includes/handler_download.php#L30
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.1.0/lib/includes/class-wpbackitup-admin.php#L1391
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.0.0/lib/includes/handler_download.php#L77
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.0.0/lib/includes/handler_download.php#L73
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.0.0/lib/includes/handler_download.php#L30
- plugins.trac.wordpress.org /browser/wp-backitup/tags/2.0.0/lib/includes/class-wpbackitup-admin.php#L1391
Sources
- CVE List CVE-2026-18386
- NVD CVE-2026-18386
Fencer Intel 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.