Clop is known for exploiting weaknesses in widely used enterprise software rather than locking systems. Instead, the group steals sensitive data and threatens to publish it unless victims pay a ransom. In this case, attackers took advantage of a previously unknown vulnerability in Oracle Corporation’s E-Business Suite software, which allowed them to access internal systems.
The breach was discovered on November 21 after the University of Phoenix appeared on Clop’s dark web leak site. Further investigation revealed that unauthorized access may have occurred as early as August 2025. The attackers used the Oracle E-Business Suite flaw to move through university systems and reach databases containing highly sensitive financial and personal records.
The vulnerability used in the attack became publicly known in November, after reports showed Clop-linked actors had been exploiting it since at least September. During that time, organizations began receiving extortion emails claiming financial and operational data had been stolen from Oracle EBS environments. This closely mirrors the methods used in the University of Phoenix breach.
The stolen data includes names, contact details, dates of birth, Social Security numbers, and bank account and routing numbers. While the university has not formally named Clop as the attacker, cybersecurity experts believe the group is responsible due to its public claims and known use of Oracle EBS vulnerabilities.
Paul Bischoff, a consumer privacy advocate at Comparitech, said the incident reflects a broader trend in which Clop has aggressively targeted flaws in enterprise software throughout the year. In response, the University of Phoenix has begun notifying affected individuals and is offering 12 months of free identity protection services, including credit monitoring, dark web surveillance, and up to $1 million in fraud reimbursement.
The breach ranks among the largest cyber incidents of 2025. Rebecca Moody, head of data research at Comparitech, said it highlights the continued risks organizations face from third-party software vulnerabilities. Security experts say the incident underscores the need for timely patching, proactive monitoring, and stronger defenses, especially in education institutions that handle large volumes of sensitive data.
