CVE-2021-20473 : Security Advisory and Response

IBM Sterling File Gateway User Interface versions 2.2.0.0 through 6.1.1.0 is impacted by a vulnerability that allows authenticated users to impersonate others after logout.

Understanding CVE-2021-20473

This CVE involves a session fixation issue in IBM Sterling File Gateway User Interface versions 2.2.0.0 through 6.1.1.0, potentially leading to privilege escalation.

What is CVE-2021-20473?

IBM Sterling File Gateway User Interface versions 2.2.0.0 through 6.1.1.0 have a flaw where sessions are not terminated post logout, enabling authenticated users to impersonate other users on the system.

The Impact of CVE-2021-20473

The vulnerability poses a medium risk with a CVSS base score of 6.3. If exploited, an attacker could gain unauthorized access to sensitive information or perform malicious actions on the system.

Technical Details of CVE-2021-20473

The vulnerability affects IBM Sterling File Gateway User Interface versions 2.2.0.0 through 6.1.1.0.

Vulnerability Description

The flaw allows authenticated users to impersonate others, risking data confidentiality and system integrity.

Affected Systems and Versions

IBM Sterling File Gateway versions 2.2.0.0, 6.0.0.0, 5.2.6.5_3, 6.0.3.4, 6.1.0.0, and 6.1.0.1 are impacted by this vulnerability.

Exploitation Mechanism

An authenticated user could exploit this flaw to take over another user's session, potentially leading to unauthorized actions.

Mitigation and Prevention

To address CVE-2021-20473, immediate actions and long-term security practices are necessary.

Immediate Steps to Take

Users should update to the fixed versions provided by IBM and ensure that sessions are properly invalidated upon logout.

Long-Term Security Practices

Regular security audits, user monitoring, and access control reviews are essential to prevent unauthorized access.

Patching and Updates

Apply official fixes released by IBM for the affected versions to mitigate the risk of session fixation vulnerability.