CVE-2026-30940

HIGH 7.2

baserCMS: Path Traversal in Theme File API Leads to Arbitrary File Write and RCE

CVSS Score

7.2

EPSS Score

0.2%

EPSS Percentile

42th

baserCMS is a website development framework. Prior to version 5.2.3, a path traversal vulnerability exists in the theme file management API (/baser/api/admin/bc-theme-file/theme_files/add.json) that allows arbitrary file write. An authenticated administrator can include ../ sequences in the path parameter to create a PHP file in an arbitrary directory outside the theme directory, which may result in remote code execution (RCE). This issue has been patched in version 5.2.3.

CWE	CWE-22 CWE-73
Vendor	baserproject
Product	basercms
Published	Mar 31, 2026
Last Updated	Apr 2, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Affected Versions

baserproject / basercms

< 5.2.3

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/baserproject/basercms/security/advisories/GHSA-c5c6-37vq-pjcq basercms.net: https://basercms.net/security/JVN_20837860 github.com: https://github.com/baserproject/basercms/releases/tag/5.2.3