What is the CVSS score of CVE-2021-29441?

CVE-2021-29441 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 74.2%.

Is there a public PoC exploit available for CVE-2021-29441?

Yes, a public proof-of-concept exploit is available for CVE-2021-29441. Prioritise patching immediately. EPSS: 74.2%.

Is there a patch available for CVE-2021-29441?

Yes, a patch is available for CVE-2021-29441. Update the affected software to the latest version immediately.

Nacos CVE-2021-29441

CRITICAL

Authentication Bypass by Spoofing (CWE-290)

2021-04-27 security-advisories@github.com

Authentication Bypass Nacos

9.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Apr 27, 2021 - 21:15 nvd

CRITICAL 9.8

Blast Radius

ecosystem impact

† from your stack dependencies † transitive graph · vuln.today resolves 4-path depth

489 maven packages depend on com.alibaba.nacos:nacos-common (1 direct, 488 indirect)

Ecosystem-wide dependent count for version 1.4.1.

DescriptionNVD

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.

AnalysisAI

Nacos is a platform designed for dynamic service discovery and configuration and service management. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

Technical ContextAI

This vulnerability is classified under CWE-290. 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. Affected products include: Alibaba Nacos. Version information: version 1.4.1.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.