CVE-2021-26073

Description

Broken Authentication in Atlassian Connect Express (ACE) from version 3.0.2 before version 6.6.0: Atlassian Connect Express is a Node.js package for building Atlassian Connect apps. Authentication between Atlassian products and the Atlassian Connect Express app occurs with a server-to-server JWT or a context JWT. Atlassian Connect Express versions from 3.0.2 before 6.6.0 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

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Vendor Advisory atlassian.com
Affected: Atlassian Atlassian Connect Express (ACE)
Published at:
Updated at:

References

Link Tags
https://confluence.atlassian.com/pages/viewpage.action?pageId=1051986099 vendor advisory
https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-a%5B%E2%80%A6%5Dypass-of-app-qsh-verification-via-context-jwts/47072
https://security.netapp.com/advisory/ntap-20210604-0004/ third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-26073?
CVE-2021-26073 has been scored as a high severity vulnerability.
How to fix CVE-2021-26073?
To fix CVE-2021-26073, 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-2021-26073 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-26073 is being actively exploited. 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-2021-26073?
CVE-2021-26073 affects Atlassian Atlassian Connect Express (ACE).
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