Improper input validation in Chimurai Http-Proxy-Middleware
CVE-2026-55602
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 class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (29.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 29.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.000
Affected products
- Chimurai Http-Proxy-Middleware — versions >= 4.0.0, < 4.1.0, >= 3.0.0, < 3.0.6, >= 0.16.0, < 2.0.10
Weakness classification (CWE)
References
- github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3… (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-55602?
- CVE-2026-55602 is a high-severity vulnerability in Chimurai Http-Proxy-Middleware, classified under Improper Input Validation. CVSS score: 8.6/10. Published 2026-06-22.
- How severe is CVE-2026-55602?
- High severity. CVSS v3 base score is 8.6 out of 10.