OpenText listed on Mimori ransomware leak site

• Ransomware group: Mimori
• Country: Canada
• Sector: Technology
• Announcement date: October 20, 2026

Mimori claims to have stolen data from OpenText

The threat actor known as Mimori has listed the technology company OpenText on its dedicated leak site. According to the announcement made on October 20, 2026, the group claims to have compromised data belonging to the organization. This type of activity is common in modern cyberattacks, where groups utilize leak sites to pressure victims by threatening to release sensitive information to the public.

The Mimori group has published a leak announcement claiming to possess a significant volume of information. The listing indicates that the group intends to release the data on October 29, 2026. While the group has publicized these claims through its platform, the specific details regarding the attack methods used to infiltrate the network remain unknown, as public information regarding the Mimori group is currently limited.

Details of the alleged data breach

The claims made by the Mimori group involve a substantial amount of data. The group asserts that it has obtained 158.8 GB of data, which consists of 94,306 files. Based on the file directory structure visible in the screenshots provided by the group, the content appears to include various types of corporate information. These include details related to account management, German operations, accounts receivable, and various test files.

The listing specifically identifies the following categories of affected data:

• Corporate financial data
• Account management information
• Operational data

In many ransomware scenarios, attackers employ a strategy known as double extortion. In this model, the threat actor not only encrypts the victim's systems to disrupt business operations but also exfiltrates sensitive data. The threat of leaking this data on a public site serves as additional leverage to demand a ransom, even if the victim has backups to restore their systems.

About OpenText

OpenText is a Canadian technology company that specializes in the development and sale of enterprise information management software. The company provides integrated platforms designed to assist businesses in managing their digital transformation processes. Their tools are intended to help organizations organize and protect their data through various management solutions.

Risk assessment and organizational implications

This incident suggests a significant risk of exposure for sensitive corporate data within OpenText. The nature of the alleged data could create secondary risks concerning the organization's operational processes and trade secrets. Because the company is based in Canada, a potential data breach of this nature could trigger legal proceedings under local data protection regulations, such as the Personal Information Protection and Electronic Documents Act (PIPEDA).

Furthermore, if the leaked data includes employee or customer information, it could facilitate identity theft and targeted phishing attacks against the individuals involved. When sensitive corporate and operational data is at risk, it can impact the trust and stability of the organization's business relationships.

For organizations operating in the technology and information management sector, maintaining robust defensive postures is critical. Common defensive steps include implementing strict access controls, maintaining comprehensive logging and monitoring to detect unauthorized data exfiltration, and ensuring that all software and systems are regularly patched. Additionally, organizations often rely on data encryption and regular offline backups to mitigate the impact of both encryption-based and exfiltration-based attacks.

Conclusion

As of the current date, the claims made by Mimori regarding the OpenText breach remain unconfirmed by the organization. However, the volume of data and the specific types of files mentioned—ranging from financial records to operational data—highlight the ongoing threat posed by ransomware groups targeting high-value technology firms.