VULNERABILITY INTELLIGENCE
CVE-2021-29441
CVSS score8.6 HIGH
EPSS probability83.25%
CISA KEVNot currently listed
Published2021-04-27
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Description
Nacos is a platform designed for dynamic service discovery and configuration and service management. In Nacos before version 1.4.1, when configured to use authentication (-Dnacos.core.auth.enabled=true) Nacos uses the AuthFilter servlet filter to enforce authentication. This filter has a backdoor that enables Nacos servers to bypass this filter and therefore skip authentication checks. This mechanism relies on the user-agent HTTP header so it can be easily spoofed. This issue may allow any user to carry out any administrative tasks on the Nacos server.
Weakness classification
- CWE-290: Authentication Bypass by Spoofing
Primary references
- security-advisories@github.com — Exploit, Third Party Advisory
- security-advisories@github.com — Exploit, Third Party Advisory
- security-advisories@github.com — Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory