Auth bypass in Atlassian Connect Spring Boot (Acsb)

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: 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.

Vulnerability class: Broken Authentication

EPSS: 0.010 (57.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-26077?
CVE-2021-26077 is a high-severity vulnerability in Atlassian Connect Spring Boot (Acsb), classified under Improper Authentication. CVSS score: 8.8/10. Published 2021-05-10.
How severe is CVE-2021-26077?
High severity. CVSS v3 base score is 8.8 out of 10.