Auth bypass in Atlassian Crowd

CVE-2017-18106

The identifier_hash for a session token in Atlassian Crowd before version 2.9.1 could potentially collide with an identifier_hash for another user or a user in a different directory, this allows remote attackers who can authenticate to Crowd or an application using Crowd for authentication to gain access to another user's session provided they can make their identifier hash collide with another user's session identifier hash.

Vulnerability class: Broken Authentication

EPSS: 0.012 (67.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2017-18106?
CVE-2017-18106 is a high-severity vulnerability in Atlassian Crowd, classified under Improper Authentication. CVSS score: 7.5/10. Published 2019-03-29.
How severe is CVE-2017-18106?
High severity. CVSS v3 base score is 7.5 out of 10.