Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
chimurai http-proxy-middleware — http-proxy-middleware `router` host+path substring matching allows Host-header-driven backend routing bypass
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV
N L N N N N L N 6.9 .0037 30.2 —
AFFECTED
Product Versions Fixed
http-proxy-middleware >= 4.0.0, < 4.1.0 – —
TIMELINE
Jun 16 Reserved by GitHub_M
Jun 22 EXPLOIT PUBLISHED — CVE-2026-55602 (chimurai http-proxy-middleware). Public exploit reference added.
Jun 22 Published (CNA: GitHub_M)
Description
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.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| June 16, 2026 | Reserved | Reserved by GitHub_M |
| June 22, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-55602 (chimurai http-proxy-middleware). Public exploit reference added. |
| June 22, 2026 | Published | Published (CNA: GitHub_M) |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| chimurai | http-proxy-middleware | — | >= 4.0.0, < 4.1.0 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-55602 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.