CVE-2026-46400

HAXCMS PHP has a File Upload Validation Bypass

Published Jun 5, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
HAX CMS helps manage microsite universe with PHP or NodeJs backends. Starting in version 11.0.6 and prior to version 25.0.0, the file upload functionality in HAXCMS PHP only validates file extensions using a regex pattern without checking the actual file content or MIME type. This allows attackers to upload malicious files (e.g., PHP webshells) disguised as legitimate image files, potentially leading to remote code execution. Version 25.0.0 contains a fix for the issue.

Analysis

AI-generated

Technical impact

The vulnerability is a file upload validation bypass in HAXCMS PHP, which allows attackers to upload files with spoofed image extensions while the content is not validated. This flaw permits the uploading of malicious PHP code that can run on the web server, leading to remote code execution if an attacker can place a script on the server. The weakness is classified as CWE‑434, a missing file type validation flaw.

Affected Systems

Affected servers are those running HAXCMS PHP versions 11.0.6 through just before 25.0.0. Users who have not upgraded beyond 25.0.0 remain exposed while using the PHP backend that supports file uploads. The fix is included in version 25.0.0 and later, making it a clear upgrade path.

Risk and Exploitability

The CVSS score of 8.7 denotes a high severity risk, and with a public upload interface the attack vector is remote over the web. Because the flaw accepts any content disguised as an image, an attacker can upload a web shell or other executable payload and trigger its execution by accessing the file via HTTP, potentially compromising the entire application. The EPSS score is not available and the vulnerability is not listed in the CISA KEV catalog, but the severity still warrants prompt action.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade HAXCMS PHP to version 25.0.0 or later to apply the fixed upload validation logic.
  • If upgrading immediately is not feasible, temporarily disable the file upload feature or restrict it to trusted users only.
  • As an additional defensive measure, configure the web server to verify MIME types and block execution of non-executable uploads on the server sides.

Generated by OpenCVE AI on June 5, 2026 at 20:36 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Haxtheweb
Haxtheweb haxcms-php
Vendors & Products Haxtheweb
Haxtheweb haxcms-php
Type Values Removed Values Added
Description HAX CMS helps manage microsite universe with PHP or NodeJs backends. Starting in version 11.0.6 and prior to version 25.0.0, the file upload functionality in HAXCMS PHP only validates file extensions using a regex pattern without checking the actual file content or MIME type. This allows attackers to upload malicious files (e.g., PHP webshells) disguised as legitimate image files, potentially leading to remote code execution. Version 25.0.0 contains a fix for the issue.
Title HAXCMS PHP has a File Upload Validation Bypass
Weaknesses CWE-434
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses
  • CWE-434

    Unrestricted Upload of File with Dangerous Type

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 8, 2026, 3:50 PM
Reserved
May 13, 2026, 9:04 PM
Status
Deferred
Published
Jun 5, 2026, 8:17 PM
Modified
Jul 23, 2026, 7:10 AM