CVE-2025-9868 is a Server-Side Request Forgery (SSRF) vulnerability classified under CWE-918, found in the Remote Browser Plugin of Sonatype Nexus Repository versions 2.0.0 up to and including 2.15.2. SSRF vulnerabilities allow attackers to induce the server to make HTTP requests to arbitrary domains, potentially accessing internal systems or sensitive data. In this case, the vulnerability enables unauthenticated remote attackers to send crafted HTTP requests that exploit the Remote Browser Plugin to exfiltrate proxy repository credentials. These credentials are critical as they allow access to proxy repositories, which are used to cache and proxy external software components, making them a valuable target for attackers aiming to compromise the software supply chain. The vulnerability does not require any authentication or user interaction, increasing its risk profile. The CVSS 4.0 base score of 8.7 reflects the high impact on confidentiality (credential exposure), no required privileges, and network attack vector. No patches or exploit code are currently publicly available, but the vulnerability is publicly disclosed and should be considered exploitable. The Remote Browser Plugin's design flaw allows the crafted requests to bypass normal access controls and retrieve sensitive information, which could be used for further attacks or lateral movement within an organization’s infrastructure.

For European organizations, the impact of CVE-2025-9868 is significant due to the potential exposure of proxy repository credentials. These credentials can grant attackers access to internal or third-party software repositories, enabling them to tamper with software components, inject malicious code, or disrupt software supply chains. This can lead to widespread compromise of development environments, build pipelines, and ultimately production systems. Confidentiality breaches of credentials can also facilitate further attacks such as lateral movement, privilege escalation, and data exfiltration. Organizations heavily reliant on Nexus Repository for artifact management, particularly in sectors like finance, manufacturing, and technology, face increased risk. The vulnerability's unauthenticated nature means attackers can exploit it remotely without prior access, increasing the attack surface. Additionally, the lack of known exploits in the wild does not reduce urgency, as public disclosure often accelerates exploit development. Disruption or compromise of software supply chains can have cascading effects on European critical infrastructure and business continuity.

1. Upgrade Nexus Repository to a version beyond 2.15.2 once Sonatype releases a patch addressing CVE-2025-9868. 2. Until a patch is available, disable or restrict access to the Remote Browser Plugin to prevent exploitation. 3. Implement strict network segmentation and firewall rules to limit outbound HTTP requests from the Nexus Repository server, reducing the ability to exfiltrate data. 4. Monitor network traffic for unusual or unauthorized outbound requests originating from Nexus Repository instances. 5. Audit and rotate proxy repository credentials regularly to minimize the impact of potential credential exposure. 6. Employ Web Application Firewalls (WAFs) with rules to detect and block SSRF attack patterns targeting Nexus Repository. 7. Conduct security awareness and incident response drills focusing on supply chain compromise scenarios. 8. Review and harden access controls around artifact repositories and related infrastructure to limit lateral movement opportunities.