CVE-2021-29441

high-risk
Published 2021-04-27

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.

Do I need to act?

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93.9% chance of exploitation in next 30 days
EPSS score — higher than 6% of all CVEs
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
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Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
8
CVSS 8.6/10 High
NETWORK / LOW complexity

Affected Products (1)

Affected Vendors

54
/ 100
high-risk
Severity 29/34 · Critical
Exploitability 20/34 · Moderate
Exposure 5/34 · Minimal