---
cve: "CVE-2021-3866"
severity: "MEDIUM"
cvss: 6.8
epss: "89%"
vendor: "zulip"
kev: false
exploited: false
published: "2022-01-20 11:15:07"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-19T13:13:00+02:00"
---

# CVE-2021-3866

> 6.8 MEDIUM · 🧪 PoC

## Beschreibung

Cross-site Scripting (XSS) - Stored in GitHub repository zulip/zulip more than and including 44f935695d452cc3fb16845a0c6af710438b153d and prior to 3eb2791c3e9695f7d37ffe84e0c2184fae665cb6.

## CVSS-Vektor

```
CVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:L/A:L
```

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

## Patch verfügbar (OSV)

- 3eb2791c3e9695f7d37ffe84e0c2184fae665cb6 (Commit)

## Referenzen

- <https://huntr.dev/bounties/5f48dac5-e112-4b23-bbbf-cc00ba83bcf2>
- <https://github.com/zulip/zulip/commit/3eb2791c3e9695f7d37ffe84e0c2184fae665cb6>
- <https://blog.zulip.com/2022/01/19/cve-2021-3866/>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-3866) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_