Someone at BrowserStack Is Leaking Users' Email Address

A developer using unique email addresses for each service discovered a direct data leak from BrowserStack to the sales platform Apollo.io. After signing up for BrowserStack's Open Source program, an email address created solely for that service began receiving unsolicited messages. Tracing the source led to Apollo, which first claimed its 'proprietary algorithm' derived the address before admitting the truth: BrowserStack, as a participating customer, had shared the developer's business contact information through its 'customer contributor network.' The date of collection was logged as February 25, 2026.

Despite BrowserStack's public 'No spam, we promise!' assurance, the company has not responded to multiple requests for comment. The incident suggests BrowserStack either sells, gives away, or has a third-party service that siphons user data to partners like Apollo. This points to a systemic, normalized trade in personal information by entities with little regard for user privacy. The developer indicates a follow-up investigation will reveal how Apollo also obtained his phone number from a major company, suggesting this breach is part of a wider pattern.