---
cve: "CVE-2021-26074"
severity: "MEDIUM"
cvss: 6.5
epss: "65%"
vendor: "Atlassian"
kev: false
exploited: false
published: "2021-04-16 03:15:12"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-08T16:02:19+02:00"
---

# CVE-2021-26074

> 6.5 MEDIUM

## Beschreibung

Broken Authentication in Atlassian Connect Spring Boot (ACSB) from version 1.1.0 before version 2.1.3: Atlassian Connect Spring Boot is a Java Spring Boot package for building Atlassian Connect apps. Authentication between Atlassian products and the Atlassian Connect Spring Boot app occurs with a server-to-server JWT or a context JWT. Atlassian Connect Spring Boot versions from version 1.1.0 before version 2.1.3 erroneously accept context JWTs in lifecycle endpoints (such as installation) where only server-to-server JWTs should be accepted, permitting an attacker to send authenticated re-installation events to an app.

## CVSS-Vektor

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

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

## Referenzen

- <https://confluence.atlassian.com/pages/viewpage.action?pageId=1051986106>
- <https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-26074) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_