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TI-2026-23765 Aliases CVE-2026-30940GHSA-c5c6-37vq-pjcq

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

Priority LOW 36CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01067 64th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed basercms (baserproject): 5.2.3baserproject/basercms (Packagist): 5.2.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
baserprojectbasercmsbefore 5.2.35.2.3Patch availableCNA
—baserproject/basercms (Packagist)before 5.2.35.2.3Patch availableGHSA-c5c6-37vq-pjcq
  • basercms Vendorbaserproject Affected before 5.2.3 Fixed in 5.2.3 Patch available CNA
  • baserproject/basercms (Packagist) Vendor— Affected before 5.2.3 Fixed in 5.2.3 Patch available GHSA-c5c6-37vq-pjcq

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:basercms:basercms:*:*:*:*:*:*:*:*before 5.2.3Vulnerablebaserproject
  • cpe:2.3:a:basercms:basercms:*:*:*:*:*:*:*:* Versions before 5.2.3 Vulnerable ·baserproject

Remediation

  • Fix · CNA basercms (baserproject) Fixed in 5.2.3
  • Fix · GHSA-c5c6-37vq-pjcq baserproject/basercms (Packagist) Fixed in 5.2.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-30940
  2. 2026-10-03 Alias added: GHSA-c5c6-37vq-pjcq

References

Exploit 1

Advisory 2

Other 2

  • TI-2026-17563 baserCMS: OS Command Injection Leading to Remote Code Execution (RCE) CVSS 3.1CRITICAL 9.1
  • TI-2025-23967 baserCMS: unsafe File Upload Leading to Remote Code Execution (RCE) CVSS 3.1HIGH 8.7
  • TI-2026-23707 baserCMS: Mail Form Acceptance Bypass via Public API CVSS 3.1MEDIUM 5.3
  • TI-2023-10935 baserCMS File Uploader Remote Code Execution (RCE) vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2023-10936 baserCMS allows any file to be uploaded CVSS 3.1CRITICAL 9.8
  • TI-2023-23483 baserCMS Code Injection Vulnerability in Mail Form Feature CVSS 3.1CRITICAL 9.8
See all 67 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences