17.5 million
A dataset containing the personally identifiable information (PII) of an estimated 17.5 million Instagram users has been leaked on the notorious hacker forum, BreachForums. The data, posted by a threat actor known as "Solonik," appears to have been collected through large-scale data scraping of Instagram's public-facing APIs rather than a direct breach of Meta's internal systems. The leaked information includes full names, email addresses, phone numbers, and user IDs. This exposure places millions of users at immediate risk of sophisticated phishing campaigns, SIM swapping, and identity theft. The incident is compounded by a reported spike in fraudulent password reset attempts against Instagram accounts, indicating that malicious actors are actively exploiting the leaked data.
Following the leak, there has been a noticeable increase in malicious activity targeting Instagram users, particularly a wave of unsolicited password reset notifications. This indicates that other threat actors are using the email addresses and phone numbers from the leak to try to hijack accounts.
Data scraping is the primary technique behind this incident. It is distinct from a "hack" in that it doesn't necessarily involve bypassing security controls to access non-public data. Instead, it automates the process of collecting data that is already publicly or semi-publicly available.
SolonikBreachForumsFor platform providers like Meta:
Settings > Security > Login Activity) for any unrecognized sessions and log them out.Users should enable MFA, preferably using an authenticator app, to protect their accounts even if their password is stolen or reset.
Mapped D3FEND Techniques:
Educate users to be vigilant against phishing attempts that will leverage the leaked data and to never click on unsolicited password reset links.
For Instagram users affected by this leak, the most critical defensive action is to enable Multi-Factor Authentication immediately. Given that the leak includes phone numbers, which makes users vulnerable to SIM swapping, it is imperative to use an authenticator app (such as Google Authenticator, Microsoft Authenticator, or Authy) for MFA instead of SMS. An app-based code is generated on the device itself and is not susceptible to interception via SIM swapping. This single step provides a powerful layer of security that protects the account even if an attacker has the user's password, directly mitigating the primary risk from this data leak.
For platform providers like Meta, preventing future large-scale scraping requires robust Application Configuration Hardening on public-facing APIs. This involves implementing adaptive rate limiting that goes beyond simple per-IP thresholds. The system should analyze behavior, detecting and throttling sources that are systematically enumerating user IDs or making an unusually high number of profile requests. Furthermore, APIs should be configured with data minimization in mind; endpoints available to unauthenticated or low-trust clients should not return sensitive PII like email addresses or phone numbers. This combination of stricter access control and reduced data exposure on public APIs is the key technical countermeasure to prevent scraping at this scale.
A dataset of 17.5 million Instagram users is posted on BreachForums by the threat actor 'Solonik'.
Users report a surge in fraudulent password reset attempts, and news outlets begin covering the leak.

Cybersecurity professional with over 10 years of specialized experience in security operations, threat intelligence, incident response, and security automation. Expertise spans SOAR/XSOAR orchestration, threat intelligence platforms, SIEM/UEBA analytics, and building cyber fusion centers. Background includes technical enablement, solution architecture for enterprise and government clients, and implementing security automation workflows across IR, TIP, and SOC use cases.
Help others stay informed about cybersecurity threats
Every tactic, technique, and sub-technique used in this threat has been identified and mapped to the MITRE ATT&CK framework for consistent, actionable threat language.
Observables and indicators of compromise (IOCs) have been extracted and cataloged. Risk has been assessed and correlated with known threat actors and historical campaigns.
Detection rules, incident response steps, and D3FEND-aligned mitigation strategies are included so your team can act on this intelligence immediately.
Structured threat data is packaged as a STIX 2.1 bundle and can be visualized as an interactive graph — relationships between actors, malware, techniques, and indicators.
Sigma detection rules are derived from the threat techniques in this article and can be converted for deployment across any major SIEM or EDR platform.