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TI-2026-34106 Aliases CVE-2026-46392

HAX CMS PHP Has a Stored XSS via Case-Sensitivity Mismatch in HTML Upload Validation

Priority HIGH 73CWE-178Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-434.

Summary

HAX CMS helps manage microsite universe with PHP or NodeJs backends. Prior to version 26.0.0 of HAX CMS PHP, the `saveFile` endpoint validates upload extensions case-insensitively and writes the filename to disk verbatim, but the `.htaccess` rule that forces `Content-Disposition: attachment` on HTML files is case-sensitive. An HTML file uploaded with an uppercase extension (`.HTML`, `.Html`, `.HTM`) is still served as `text/html` but the forced-download header never applies, so the browser renders it inline and executes any embedded JavaScript in the HAXcms origin. This bypasses the mitigation shipped for CVE-2026-22704. Version 26.0.0 contains a fix.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00272 19th percentileScored 2026-11-07
Fix Fixed haxcms-php (haxtheweb): 26.0.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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
haxthewebhaxcms-phpbefore 26.0.026.0.0Patch availableCNA
  • haxcms-php Vendorhaxtheweb Affected before 26.0.0 Fixed in 26.0.0 Patch available CNA

Remediation

  • Fix · CNA haxcms-php (haxtheweb) Fixed in 26.0.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-46392

References

Other 1

  • TI-2026-34109 HAX CMS Vulnerable to Private Key Disclosure via Broken HMAC Implementation CVSS 4.0CRITICAL 9.3
  • TI-2026-34105 HAX open-apis: Credential Theft via Server-Side Request Forgery (SSRF) in open-apis CVSS 4.0HIGH 8.7
  • TI-2026-27339 HAX CMS's public /server-status endpoint exposes authentication tokens, user activity, and client IP addresses CVSS 4.0HIGH 8.7
  • TI-2026-34113 Authenticated Remote Code Execution via File Overwrite CVSS 4.0CRITICAL 9.4
  • TI-2025-23152 HAX CMS PHP allows Insecure File Upload to Lead to Remote Code Execution CVSS 3.1CRITICAL 10.0
  • TI-2026-34194 HAX CMS: Stored XSS via '<video-player>' component allows arbitrary JavaScript execution and token theft CVSS 4.0CRITICAL 9.3
See all 32 →

Sources

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