Auth bypass in Atlassian Connect Express (Ace)
CVE-2021-26073
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.
Vulnerability class: Broken Authentication
EPSS: 0.009 (56.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N.
Affected products
- Atlassian Connect Express (Ace) — versions 3.0.2, unspecified
- Atlassian Connect_express
Weakness classification (CWE)
References
- security@atlassian.com (x_refsource_MISC, Vendor Advisory)
- security@atlassian.com (x_refsource_MISC)
- security@atlassian.com (x_refsource_CONFIRM, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-26073?
- CVE-2021-26073 is a high-severity vulnerability in Atlassian Connect Express (Ace), classified under Improper Authentication. CVSS score: 7.7/10. Published 2021-04-16.
- How severe is CVE-2021-26073?
- High severity. CVSS v3 base score is 7.7 out of 10.