Summary
Multiple functions conduct substring-only matching to validate hostnames to which basic authorization should be sent. An attacker can append the matched substrings to an attacker-controlled endpoint and capture authentication.
Details
api/services/website/cacheAddress.js, api/apps/haxcms/lib/JOSHelpers.js, and api/apps/haxcms/convert/elmslnToSite.js use similar logic to check for hard-coded site names. However, the logic only looks for the substring to be included in the user-controlled string, allowing an attacker to craft an API call and extract the credentials intended for the hard-coded domains.
PoC
Making API calls to an affected endpoint will result in credential theft. The attacker-controlled domains in these proofs of concept are cloudflared tunnels, protecting the production credentials from unencrypted exposure.
cacheAddress.js:
elmslnToSite.js:
JOSHelpers.js:
Impact
This vulnerability allows internal data, including secrets, to be exfiltrated to an attacker-controlled domain. Credentials were confirmed with the maintainer to grant access to unreleased LMS content on subsequent systems; out of scope for PoC.
Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-46391? CVE-2026-46391 is a high-severity server-side request forgery (SSRF) vulnerability in @haxtheweb/open-apis (npm), affecting versions < 26.0.0. It is fixed in 26.0.0. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
- Which versions of @haxtheweb/open-apis are affected by CVE-2026-46391? @haxtheweb/open-apis (npm) versions < 26.0.0 is affected.
- Is there a fix for CVE-2026-46391? Yes. CVE-2026-46391 is fixed in 26.0.0. Upgrade to this version or later.
- Is CVE-2026-46391 exploitable, and should I be worried? Whether CVE-2026-46391 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-46391 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-46391? Upgrade
@haxtheweb/open-apisto 26.0.0 or later.