CVE-2021-29441 - CVE House
Back to Database
Status published High CVE-2021-29441

Authentication bypass

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2021-29441

Credits & Attribution

No credits recorded in the NVD database.

References

More from alibaba

View All →
CVE-2021-44667
A Cross Site Scripting (XSS) vulnerability exists in Nacos 2.0.3...
Medium 6.1
CVE-2021-43116
An Access Control vulnerability exists in Nacos 2.0.3 in the...
High 8.8
CVE-2021-29442
Authentication bypass
High 8.6
CVE-2020-21699
The web server Tengine 2.2.2 developed in the Nginx version...
High 7.5
CVE-2020-19676
Nacos 1.1.4 is affected by: Incorrect Access Control. An environment...
Medium 5.3

Affected Vendor

Affected Software

nacos
Vulnerable Versions:
< 1.4.1

Timeline

Official Publish: April 27th, 2021
Last Modified: August 3rd, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Weaknesses (CWE)

CWE-290

MITRE ATT&CK TTPs

T1557 Adversary-in-the-Middle
Collection
T1078 Valid Accounts
Persistence
T1550 Use Alternate Authentication Material
Defense Evasion
T1021 Remote Services
Lateral Movement
T1190 Exploit Public-Facing Application
Initial Access