What is the CVSS score of EUVD-2026-17267?

EUVD-2026-17267 has a CVSS 3.1 base score of 7.2 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.2%.

Which versions of PHP are affected by EUVD-2026-17267?

baserCMS versions prior to 5.2.3 contain an authenticated path traversal vulnerability in the theme file management API that allows compromised administrator accounts to execute arbitrary code on the…. A patch is available.

How to fix or mitigate EUVD-2026-17267?

Within 24 hours: Audit baserCMS installations to identify instances running versions prior to 5.2.3 and document all systems. Within 7 days: Enforce enhanced access controls for administrator accounts, including mandatory multi-factor authentication and IP whitelisting for admin portal access. Within 30 days: Contact baserCMS vendor for patch availability timeline; if no patch is released, migrate to alternative CMS solutions or implement the compensating controls listed below.

PHP EUVD-2026-17267

| CVE-2026-30940 HIGH

Path Traversal (CWE-22)

2026-03-31 GitHub_M

GHSA-c5c6-37vq-pjcq

RCE Path Traversal PHP

7.2

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

7.2 HIGH

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

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

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

Lifecycle Timeline

Patch released

Apr 01, 2026 - 02:30 nvd

Patch available

EUVD ID Assigned

Mar 31, 2026 - 01:00 euvd

EUVD-2026-17267

Analysis Generated

Mar 31, 2026 - 01:00 vuln.today

CVE Published

Mar 31, 2026 - 00:45 nvd

HIGH 7.2

DescriptionGitHub Advisory

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.

AnalysisAI

Authenticated path traversal in baserCMS theme file management API (versions prior to 5.2.3) enables arbitrary file write, allowing administrators to create malicious PHP files outside the theme directory and achieve remote code execution. The vulnerability (CWE-22) requires high privileges (PR:H) but has low attack complexity (AC:L) with network access (AV:N). CVSS score of 7.2 reflects the significant impact when administrator credentials are compromised. No public exploit code or CISA KEV listing identified at time of analysis, though the technical details in the advisory provide sufficient information for weaponization.

Technical ContextAI

baserCMS is a PHP-based website development framework. The vulnerability exists in the theme file management API endpoint (/baser/api/admin/bc-theme-file/theme_files/add.json) which fails to properly sanitize user-supplied path parameters. The root cause is a classic path traversal (CWE-22) vulnerability where the API accepts directory traversal sequences (../) in the path parameter without adequate validation or canonicalization. This allows an authenticated administrator to escape the intended theme directory constraints and write files to arbitrary filesystem locations. Since baserCMS is a PHP application, an attacker can write executable PHP code to web-accessible directories, converting the arbitrary file write primitive into remote code execution. The affected CPE (cpe:2.3:a:baserproject:basercms) covers all versions prior to the patched release 5.2.3.

RemediationAI

Vendor-released patch: baserCMS version 5.2.3 addresses this vulnerability and should be deployed immediately. Organizations should upgrade all baserCMS instances to version 5.2.3 or later using the official release available at https://github.com/baserproject/basercms/releases/tag/5.2.3. Prior to patching, review administrator access logs for suspicious theme file upload activity, particularly API requests to the /baser/api/admin/bc-theme-file/theme_files/add.json endpoint with unusual path parameters containing directory traversal sequences. As a temporary risk mitigation measure until patching is complete, restrict administrator account access through network segmentation, implement additional authentication controls (MFA), and monitor filesystem integrity for unexpected PHP files in non-theme directories. Consult the official security advisory at https://basercms.net/security/JVN_20837860 for additional vendor guidance.