CVE-2026-114622
Deferred
Deferred - Pending Action
Path Traversal in baserCMS via BcThemeFile Plugin
Vulnerability report for CVE-2026-114622, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-23
Last updated on: 2026-10-23
Assigner: GitHub, Inc.
Description
Description
baserCMS is a website development framework. In versions 5.2.3 before 5.3.2 and 5.4.0 before 5.4.2, the optional BcThemeFile plugin's Admin API validates a raw path in ThemeFilesService::update() and getFullpath(), but ThemeFileForm::_execute() subsequently applies rawurldecode() to fullpath before writing. Because normalizePath() resolves only literal dot segments, percent-encoded traversal can pass the containment checks and become a path outside the theme directory at the write sink. An authenticated administrator can write PHP files into writable locations such as webroot and execute them, exceeding the intended theme-template editing boundary. The source also identifies the same check-before-decode ordering in ThemeFilesService::copy(), although that path was not dynamically verified. Exploitation requires the non-default plugin, an administrator session, and a same-origin Origin header; USE_CORE_ADMIN_API=false does not block session-authenticated requests. The Admin web form is not affected by this encoded-path tampering because FormProtection protects fullpath. This is a third bypass of the protections associated with CVE-2026-30940, using encoded traversal decoded after validation. This issue has been patched in versions 5.3.2 and 5.4.2.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| baserproject | basercms | >= 5.2.3, < 5.3.2 |
| baserproject | basercms | >= 5.4.0, < 5.4.2 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-180 | The product validates input before it is canonicalized, which prevents the product from detecting data that becomes invalid after the canonicalization step. |
| CWE-22 | The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. |