Cl0P Ransomware Group Exploits Oracle EBS Zero-Day to Breach Entrust
The Cl0P ransomware group has recently claimed responsibility for a significant cyberattack on Entrust, a leading digital security firm. This breach was facilitated by exploiting a critical zero-day vulnerability in Oracle’s E-Business Suite (EBS), specifically identified as CVE-2025-61882.
Details of the Breach
Cl0P announced the breach on their dark web leak site, stating that they gained unauthorized access to Entrust’s systems through an unpatched flaw in Oracle EBS. This vulnerability allows remote code execution without the need for authentication, making it particularly dangerous. The flaw affects multiple versions of EBS, a platform widely used for financial and supply chain management.
Oracle addressed this vulnerability in their October 2025 Critical Patch Update. However, delayed adoption of this patch has left many organizations, including Entrust, exposed to potential attacks.
Entrust’s Response
Entrust, known for providing identity and access management solutions, confirmed the incident in a brief statement. The company noted that, as of now, there is no evidence to suggest that customer data has been compromised. They are conducting a thorough investigation and have implemented enhanced security measures to prevent future incidents.
Cl0P’s Tactics and Impact
This attack is part of a broader campaign by Cl0P, which has been exploiting CVE-2025-61882 since its disclosure in September 2025. The group has listed over a dozen victims, including major manufacturing companies and financial institutions. Their strategy involves exfiltrating data before encrypting it, allowing them to demand ransoms while also pressuring victims through public exposure.
Analysts at Mandiant have observed that Cl0P is shifting towards targeting vulnerabilities in legacy enterprise systems, a tactic often referred to as big game hunting. This approach focuses on exploiting known vulnerabilities in widely used systems to maximize impact and potential ransom payouts.
Supply Chain Security Concerns
The breach of Entrust underscores the ongoing risks associated with supply chain security. Organizations that rely on Oracle EBS are urged to prioritize patching and conduct comprehensive vulnerability assessments. The incident serves as a stark reminder of the importance of proactive threat detection and response strategies in the face of increasingly sophisticated ransomware operations.
Recommendations for Organizations
1. Immediate Patching: Ensure that all systems are updated with the latest security patches, particularly those addressing CVE-2025-61882.
2. Vulnerability Assessments: Conduct regular scans to identify and remediate potential vulnerabilities within your network.
3. Enhanced Monitoring: Implement advanced monitoring tools to detect unusual activities that may indicate a breach.
4. Employee Training: Educate staff on recognizing phishing attempts and other common attack vectors used by ransomware groups.
5. Incident Response Planning: Develop and regularly update an incident response plan to ensure a swift and effective reaction to potential breaches.
Conclusion
The Cl0P ransomware group’s exploitation of the Oracle EBS zero-day vulnerability to breach Entrust highlights the critical need for organizations to stay vigilant and proactive in their cybersecurity efforts. By promptly applying patches, conducting regular security assessments, and fostering a culture of security awareness, companies can better protect themselves against such sophisticated threats.
