VULNERABILITY INTELLIGENCE

CVE-2021-4236

CVSS score9.8 CRITICAL

EPSS probability1.19%

CISA KEVNot currently listed

Published2022-12-27

Last modified2026-06-17

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

Description

Web Sockets do not execute any AuthenticateMethod methods which may be set, leading to a nil pointer dereference if the returned UserData pointer is assumed to be non-nil, or authentication bypass. This issue only affects WebSockets with an AuthenticateMethod hook. Request handlers that do not explicitly use WebSockets are not vulnerable.

Weakness classification

nvd@nist.gov: CWE-476

Primary references

security@golang.org — Patch, Third Party Advisory
security@golang.org — Exploit, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Exploit, Patch, Third Party Advisory