CVE-2017-18106 Explained : Impact and Mitigation

Atlassian Crowd before version 2.9.1 is vulnerable to a cryptographic algorithm collision issue that could allow remote attackers unauthorized access to user sessions.

Understanding CVE-2017-18106

This CVE describes a security vulnerability in Atlassian Crowd that could be exploited by attackers to gain unauthorized access to user sessions.

What is CVE-2017-18106?

The vulnerability in Atlassian Crowd before version 2.9.1 allows remote attackers to manipulate identifier hashes to access other users' sessions.

The Impact of CVE-2017-18106

Attackers who can authenticate to Crowd or an application using Crowd for authentication can exploit this vulnerability to gain unauthorized access to user sessions.

Technical Details of CVE-2017-18106

Atlassian Crowd's vulnerability is detailed below:

Vulnerability Description

Before version 2.9.1, a collision between identifier hashes could lead to unauthorized access to user sessions.

Affected Systems and Versions

Product: Crowd
Vendor: Atlassian
Versions Affected: < 2.9.1 (unspecified/custom)

Exploitation Mechanism

Remote attackers can manipulate identifier hashes to collide with other users' session identifier hashes, granting them unauthorized access.

Mitigation and Prevention

To address CVE-2017-18106, follow these steps:

Immediate Steps to Take

Upgrade Atlassian Crowd to version 2.9.1 or newer.
Monitor for any unauthorized access or suspicious activities.

Long-Term Security Practices

Implement multi-factor authentication for enhanced security.
Regularly review and update cryptographic algorithms and security protocols.

Patching and Updates

Apply security patches and updates promptly to mitigate known vulnerabilities.