HIGH CWE-290
CVE-2021-29441
Authentication bypass
Alibaba·nacos
8.6/ 10
CVSS 3.1
High severity
83%
EPSS exploit odds
Chance of exploitation in the next 30 days
Higher than 99.7% of all CVEs
Not listed
CISA KEV catalog
No confirmed in-the-wild exploitation on CISA's list.
Timeline
- Published
- Apr 27, 2021
- Updated
- Aug 3, 2024
- First covered
- Jul 3, 2026
- Latest story
- 4 months ago
Summary
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.
CWE-290Authentication Bypass by Spoofing
Attack profile
Attack vectorNetwork
ComplexityLow
PrivilegesNone
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:NAffected products
- Alibaba nacos< 1.4.1