CVE-2021-29441

Public Exploit
Authentication bypass

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 94.05% Top 5%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: alibaba nacos
Published at:
Updated at:

References

Link Tags
https://github.com/alibaba/nacos/issues/4701 third party advisory exploit
https://github.com/advisories/GHSA-36hp-jr8h-556f third party advisory exploit
https://github.com/alibaba/nacos/pull/4703 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-29441?
CVE-2021-29441 has been scored as a high severity vulnerability.
How to fix CVE-2021-29441?
To fix CVE-2021-29441, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-29441 being actively exploited in the wild?
It is possible that CVE-2021-29441 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~94% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29441?
CVE-2021-29441 affects alibaba nacos.
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