Partial String Comparison Affecting http-proxy-middleware package, versions >=0.16.0 <2.0.10>=3.0.0 <3.0.6>=4.0.0 <4.1.0
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-HTTPPROXYMIDDLEWARE-17375053
- published18 Jun 2026
- disclosed18 Jun 2026
- creditStr1ckl4nd, 7thParkk
Introduced: 18 Jun 2026
NewCVE-2026-55602 (opens in a new tab)How to fix?
Upgrade http-proxy-middleware to version 2.0.10, 3.0.6, 4.1.0 or higher.
Overview
Affected versions of this package are vulnerable to Partial String Comparison via the router component. An attacker can route requests to unintended backend servers by sending crafted HTTP requests with manipulated Host headers.