CVE-2026-91143

high

goproxy through 15.3 fails to apply HTTP proxy basic authentication to CONNECT tunnel requests, allowing unauthenticated clients to bypass credential requireme…

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.

CVSS

7.2

7.2 (CVSS v3.1)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Severity source: NVD CVSS v3.1 (disclosure@vulncheck.com)

Timeline (UTC)

Published: 2026-09-14 22:16

Modified: 2026-09-23 17:17

NVD status: Deferred

Last synced 1 day ago

Verified against the source API 2026-10-27 06:53 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

Not reported by the source (unknown — not "none").

Weakness classification (CWE)

CWE-288

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

https://github.com/geo-chen/oss/blob/main/goproxy.md disclosure@vulncheck.com
https://github.com/snail007/goproxy disclosure@vulncheck.com
https://github.com/snail007/goproxy/blob/v15.3/services/http.go disclosure@vulncheck.com
https://github.com/snail007/goproxy/blob/v15.3/utils/structs.go disclosure@vulncheck.com
https://www.vulncheck.com/advisories/goproxy-through-15.3-authentication-bypass-via-connec... disclosure@vulncheck.com

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:53 UTC · record ↗

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