High8.8Atlassian

High [CVE-2021-26077] Broken Authentication in Atlassian Connect Spring Boot (ACSB) in version 1.1.0 before 2.1.3 and from version 2.1.4 before 2.1.5…

This high-severity Atlassian advisory covers CVE-2021-26077.

CVE-2021-26077 Published May 10, 2021Updated by vendor Jun 17, 2026

CVE-2021-26077

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Summary

Broken Authentication in Atlassian Connect Spring Boot (ACSB) in version 1.1.0 before 2.1.3 and from version 2.1.4 before 2.1.5: 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 1.1.0 before 2.1.3 and versions 2.1.4 before 2.1.5 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.

Affected versions

1.1.0
2.1.4

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Fixed versions

2.1.3
2.1.5

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Mitigation

Upgrade to a fixed release: 2.1.3, 2.1.5. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Discussion(0)

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