CVE-2026-55602
HighCVSS 8.6Exploitation Probability (EPSS)
Low risk31th percentile - higher than 31% of all known CVEs
Summary
Vulnerability in http-proxy-middleware from version 0.16.0 to 2.0.10, 3.0.6, and 4.1.0 involves incorrect matching of host+path router entries. The implementation uses unanchored substring matching instead of full matching, allowing an attacker to route requests to an unintended backend via a crafted Host header.
Risk Assessment
An attacker can bypass routing rules and redirect requests to an unauthorized backend, potentially leading to data disclosure, integrity compromise, or further attacks on internal systems.
Recommendation
Immediately update http-proxy-middleware to version 2.0.10, 3.0.6, or 4.1.0, depending on the major version in use.
Related vulnerabilities
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Sandbox escape vulnerability due to use-after-free in the Widget: Gtk component of Firefox. It may allow bypassing process isolation. The vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.
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- CVE-2026-124900Critical
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- CVE-2026-124864Critical
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- CVE-2026-124861Critical
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- CVE-2026-124859Critical
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- CVE-2026-124853Critical
A sandbox escape vulnerability due to incorrect boundary conditions exists in the Graphics: Text component of Firefox. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, and Firefox ESR 153.7.
- CVE-2026-119446Critical
A Session Fixation vulnerability in the CLI login flow in nerves_hub_web allows an unauthenticated attacker to obtain an API token for another user's account via a crafted login link. The confirmation code is only displayed and never compared, so it cannot prove that the confirming person is the one who started the login.
- CVE-2026-60043Critical
An unauthenticated remote attacker can perform an XSS attack on a logged-in backend user, allowing execution of multiple critical system actions such as shutting down the server or restoring an uploaded backup.
- CVE-2026-13312Critical
The described vulnerability could allow an attacker to compromise a system. Technical details are not provided in the description.
Original NVD description (English source)
http-proxy-middleware is node.js http-proxy middleware. From 0.16.0 until 2.0.10, 3.0.6, and 4.1.0, http-proxy-middleware documents router proxy-table entries as host, path, or host+path selectors, but the host+path implementation uses unanchored substring matching on attacker-controlled request metadata. As a result, a crafted Host header that is only a superstring match for a configured host+path key can still route a request to an unintended backend. This vulnerability is fixed in 2.0.10, 3.0.6, and 4.1.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS