A high severity privilege escalation vulnerability in Sonatype Nexus Repository 3 allows authenticated attackers to gain unauthorized administrative access.

This vulnerability (CWE-843) involves type confusion within the REST privileges API, which can be exploited by an authenticated user with low privileges to escalate their permissions.

Successful exploitation allows an attacker to gain elevated privileges within the Nexus Repository, potentially leading to full administrative control over the application. Given the CVSS score of 8.6, this represents a significant risk to the integrity and availability of software supply chain assets stored within the repository. Unauthorized access could result in the compromise of proprietary source code, malicious injection of artifacts, or complete system takeover.

Immediate Action: Update Sonatype Nexus Repository 3 to version 3.95.0 or later immediately to resolve the vulnerable API logic.

Proactive Monitoring: Review audit logs for suspicious activity involving the REST privileges API, particularly focusing on unexpected permission changes or privilege escalation attempts by standard user accounts.

Compensating Controls: Restrict access to the Nexus Repository REST API to trusted internal IP addresses and implement robust identity and access management policies to limit the potential impact of credential compromise.

Public Exploit Available: Unknown.

This vulnerability presents a high risk to organizational security due to the potential for complete privilege escalation. Administrators should prioritize updating the software to version 3.95.0 as soon as possible to neutralize this threat.