Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-91143

CVE-2026-91143MEDIUM

snail007 goproxy — goproxy through 15.3 Authentication Bypass via CONNECT

  AV  AC  AT  PR  UI  VC  VI  VA   CVSS    EPSS   %ile   KEV
   N   L   N   N   N   N   N   N    6.9   .0047   38.1     —

AFFECTED
  Product  Versions     Fixed
  goproxy  unspecified  —

TIMELINE
  Sep 14  Reserved by VulnCheck
  Sep 14  Published (CNA: VulnCheck)
  Sep 15  EXPLOIT PUBLISHED — CVE-2026-91143 (snail007 goproxy). Public exploit reference added.
  Sep 24  EXPLOIT PUBLISHED — CVE-2026-91143 (snail007 goproxy). Public exploit reference added.

CWE-288 · CNA: VulnCheck · CVSS v4.0 · 5 references · NVD status: Deferred

Description

goproxy through 15.3 fails to apply HTTP proxy basic authentication to CONNECT tunnel requests, allowing unauthenticated clients to bypass credential requirements. Attackers can issue CONNECT requests to establish tunnels through the authenticated proxy without providing credentials, enabling arbitrary TCP traffic relay and access to restricted destinations.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
September 14, 2026	Reserved	Reserved by VulnCheck
September 14, 2026	Published	Published (CNA: VulnCheck)
September 15, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-91143 (snail007 goproxy). Public exploit reference added.
September 24, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-91143 (snail007 goproxy). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
snail007	goproxy	—	—	—

Weaknesses

CWE-288

References (5)

https://github.com/geo-chen/oss/blob/main/goproxy.md [third-party-advisory, exploit]
https://github.com/snail007/goproxy [product]
https://github.com/snail007/goproxy/blob/v15.3/services/http.go [technical-description]
https://github.com/snail007/goproxy/blob/v15.3/utils/structs.go [technical-description]
https://www.vulncheck.com/advisories/goproxy-through-15.3-authentication-bypass-via-connect [third-party-advisory]

Authoritative record: CVE-2026-91143 at cve.org

Vendors: snail007

Weaknesses: CWE-288

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-91143 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 Saturday, October 3, 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.