Security Bulletin: Potential spoofing attack in WebSphere Application Server (CVE-2020-4421)

Summary

IBM WebSphere Application Server Liberty using openidConnectServer feature could allow spoofing identity by an authenticated user. This has been addressed.

Vulnerability Details

CVEID:CVE-2020-4421
**DESCRIPTION:**IBM WebSphere Application Liberty could allow an authenticated user using openidconnect to spoof another users identify.
CVSS Base score: 5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/180084 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L)

Affected Products and Versions

Remediation/Fixes

The recommended solution is to apply the interim fix or FixPack containing APAR PH24154 for each named product as soon as practical.

For WebSphere Application Server Liberty 19.0.0.5-20.0.0.4 using the openidConnectServer-1.0 feature:
· Upgrade to minimal fix pack levels as required by interim fix and then apply Interim Fix PH24154
--OR–
· Apply Liberty Fix Pack 20.0.0.5 or later.

Additional interim fixes may be available and linked off the interim fix download page.

Workarounds and Mitigations

None