CVE-2021-26073 Broken Authentication in Atlassian Connect Express
An attacker can bypass authentication in Atlassian Connect Express by sending context JWTs to lifecycle endpoints, allowing unauthorized re-installation events.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-26073?
CVE-2021-26073 is a high-severity authentication bypass vulnerability in Atlassian Connect Express (ACE), published on 16 Apr 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-287
Which versions are affected by CVE-2021-26073?
2 open source packages ship an affected version, including atlassian-connect-express. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
atlassian-connect-express npm | From 3.0.2 | 6.6.0 |
atlassian-connect-express npm | From 3.0.2 | 6.6.0 |
Products include Atlassian Connect Express.
How do I fix CVE-2021-26073?
Upgrade atlassian-connect-express to 6.6.0 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2021-26073 being exploited?
There is no known exploitation of CVE-2021-26073 in the wild and no public exploit code.
Sources
Also known as GHSA-4v96-m8xv-x83v.