Nacos < 1.4.1 Authentication Bypass (CVE-2021-29441)

critical Nessus Plugin ID 154416

Synopsis

The web application running on the remote web server is affected by authentication bypass vulnerability.

Description

A change introduced in Nacos prior to 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.

Solution

Upgrade to Nacos 1.4.1 or later

See Also

http://www.nessus.org/u?07734abc

https://github.com/alibaba/nacos/issues/4701

Plugin Details

Severity: Critical

ID: 154416

File Name: nacos_cve-2021-29441.nbin

Version: 1.39

Type: remote

Family: Web Servers

Published: 10/26/2021

Updated: 3/19/2024

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.9

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-29441

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:nacos:nacos

Required KB Items: installed_sw/Nacos

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/27/2021

Vulnerability Publication Date: 4/27/2021

Reference Information

CVE: CVE-2021-29441

CWE: 290