CVE-2021-26077

Public Exploit

Description

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.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.41%
Vendor Advisory atlassian.com Vendor Advisory atlassian.com
Affected: Atlassian Atlassian Connect Spring Boot (ACSB)
Published at:
Updated at:

References

Link Tags
https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072 issue tracking exploit vendor advisory
https://confluence.atlassian.com/pages/viewpage.action?pageId=1063555147 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-26077?
CVE-2021-26077 has been scored as a high severity vulnerability.
How to fix CVE-2021-26077?
To fix CVE-2021-26077, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-26077 being actively exploited in the wild?
It is possible that CVE-2021-26077 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-26077?
CVE-2021-26077 affects Atlassian Atlassian Connect Spring Boot (ACSB).
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