OpenAI warns some users that a cyberattack on analytics firm Mixpanel may have exposed their data.
Mixpanel is a product analytics platform that companies use to understand how people interact with their apps or websites.
Many tech companies use Mixpanel to make data-driven decisions about features, performance, and customer journeys.
OpenAI is alerting some users about potential exposure in a data breach at Mixpanel. The analytics provider reported a smishing attack detected on November 8, but attempted to downplay the security breach by saying that it impacted a limited number of customers.
OpenAI says its systems weren’t breached and ChatGPT chats, prompts, API data, passwords, keys, and payment info remain safe. The attacker instead stole a limited Mixpanel dataset containing user profile details from platform.openai.com—name, email, rough location, OS/browser info, organization or user ID, and referring website. OpenAI warns this data could fuel phishing and social-engineering attempts.
“As part of our security investigation, we removed Mixpanel from our production services, reviewed the affected datasets, and are working closely with Mixpanel and other partners to fully understand the incident and its scope. We are in the process of notifying impacted organizations, admins, and users directly. While we have found no evidence of any effect on systems or data outside Mixpanel’s environment, we continue to monitor closely for any signs of misuse,” OpenAI said.
In response, OpenAI removed Mixpanel from production, reviewed affected data, and is notifying impacted users and organizations while continuing to monitor for misuse.
“On November 8th, 2025, Mixpanel detected a smishing campaign and promptly executed our incident response processes.” reads the data breach notification published by Mixpanel. “We took comprehensive steps to contain and eradicate unauthorized access and secure impacted user accounts. We engaged external cybersecurity partners to remediate and respond to the incident.”
Mixpanel took several steps to secure its systems and protect affected customers. The company secured compromised accounts, revoked all active sessions, and rotated exposed credentials. It blocked the malicious IP addresses involved in the attack and added indicators of compromise to its security monitoring platform.
To strengthen internal security, Mixpanel performed global password resets for all employees and brought in a third-party forensics team to help with containment and cleanup. It also conducted a detailed forensic review of authentication, session, and export logs related to affected accounts.
To prevent similar incidents, Mixpanel implemented new controls designed to detect and block this kind of malicious activity in the future. The company is also working with law enforcement and external cybersecurity advisors.
Customers who received a notification from Mixpanel should follow the instructions included in that message. Those who did not receive any communication were not impacted and do not need to take further action.
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Pierluigi Paganini
(SecurityAffairs – hacking, OpenAI)