CVE-2026-114622baserCMS: Encoded path traversal bypass in the theme file API
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EPSS puts the chance of exploitation in the next 30 days at 0.49%, higher than 42% of scored CVEs.
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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
- 7.2 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-22, CWE-180
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.49% (percentile 42)
- Assigned by
- GitHub_M
- NVD analysis
- Deferred
- Record last updated
- Oct 23, 2026
- First seen by InfoSec Signals
- Oct 23, 2026
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.