CVE-2026-46391
Published: 05 June 2026
Summary
CVE-2026-46391 is a high-severity Permissive List of Allowed Inputs (CWE-183) vulnerability. Its CVSS base score is 8.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Forced Authentication (T1187); ranked at the 36.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
OWASP Top 10 for Web (2025)
EU & UK References
No EU or UK CSIRT advisories indexed for this CVE.
Vulnerability details
HAX CMS helps manage microsite universe with PHP or NodeJs backends. Starting in version 9.0.1 and prior to version 26.0.0 of @haxtheweb/open-apis, multiple functions conduct substring-only matching to validate hostnames to which basic authorization should be sent. An attacker can…
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append the matched substrings to an attacker-controlled endpoint and capture authentication. Version 26.0.0 fixes the issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Substring hostname validation flaw (CWE-183/918) directly enables forced basic-auth credential capture to attacker endpoint.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing attempts server-side requests to internal resources, identifying SSRF weaknesses for remediation.
Outbound connections to external resources can be monitored and limited at the boundary, reducing SSRF impact.
Validates server-side URLs and resource references to block SSRF attempts.
Detects server-side request forgery through monitoring of unexpected outbound connections.