---
cve: "CVE-2021-29441"
severity: "HIGH"
cvss: 8.6
epss: "87.8%"
vendor: "alibaba"
kev: false
exploited: false
published: "2021-04-27 21:15:07"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-03T08:39:04+02:00"
---

# CVE-2021-29441

> 8.6 HIGH · 🧪 PoC

## Beschreibung

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.

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Verändert | bad |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Keine | good |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 1d88d5d773c46912957a15cb6e78bd8b01c89fde (Commit)

## Referenzen

- <https://github.com/alibaba/nacos/issues/4701>
- <https://github.com/advisories/GHSA-36hp-jr8h-556f>
- <https://github.com/alibaba/nacos/pull/4703>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-29441) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_