Summary

  • Total number of incidents disclosed: 44
  • Total number of known breached records: 1,443,150,467

Sources of breached data

  • Scraped or leaked from public APIs:
    • Facebook (1.2 billion records)

    • Credential dump compiled via infostealers (184 million+ credentials)

  • Vendor/Cloud breaches exposing customer/employee data

    • Ascension Health (via third-party file tool): 437,000
    • Spyware apps (stalkerware): 3.2 million

  • Direct or insider breaches involving client data:

    • AT&T (unconfirmed): 31 million
    • Coinbase (insider at call centre): 69,461
    • Co-op UK (ransomware gang): claimed 20 million

Top 5 incidents by number of records affected

The following are the largest incidents publicly disclosed in May 2025, ranked by known/claimed impact:

1. Facebook (Meta)

  • Records affected: 1.2 billion.
  • Data: Full names, Facebook IDs, email addresses, phone numbers, locations, birthdates and gender.
  • Cause: Scraped via a vulnerable Facebook API.
  • Status: Yet to be verified – Meta claims it relates to a historic breach.

2. Unknown credentials database

  • Records affected: 184,162,718 email/password pairs
  • Data: Plaintext credentials tied to Google, Microsoft and Meta, and banking logins
  • Cause: Likely compiled from infostealer malware and left exposed online
  • Status: Removed after discovery, source undetermined

3. AT&T (unverified)

  • Records affected: 31 million (claimed).
  • Data: Names, birthdates, addresses, phone numbers, tax IDs, device and cookie data.
  • Cause: Posted to a hacking forum.
  • Status: So far unverified but sample data was provided. AT&T is investigating.

4. Co-op UK

  • Records affected: ~20 million (claimed by attackers).
  • Data: Names, dates of birth, contact details of current and former members.
  • Cause: Ransomware gang DragonForce (linked to Scattered Spider).
  • Status: Under investigation.

5. LexisNexis Risk Solutions

  • Records affected: 364,000 individuals.
  • Data: Full names, home addresses, dates of birth, Social Security numbers, and potentially employment/salary information.
  • Cause: Data breach stemming from a hacking incident in December 2024, when attackers infiltrated internal systems and accessed personal records.
  • Status: Breach discovered in January 2025 and disclosed in May 2025 after investigation. Affected individuals were offered credit monitoring.

Trends in May 2025

  • Significant rise in scraped/mass-exposed data
    Two of the five largest leaks came from large-scale scraping or credential aggregation (Facebook and infostealer dumps), rather than direct intrusions.
  • Vendor risk and insider breaches rising
    Incidents at Ascension Health, Adidas, and Coinbase all stemmed from third parties – either contractors or software dependencies.
  • Retail and tech remain prime targets
    Retailers including Co-op, Harrods, Adidas, Dior, and Victoria’s Secret were targeted or affected this month. Cloud services (TeleMessage, spyware vendors) and edtech (Pearson) also saw notable activity.
  • UK particularly affected
    More than 5 major incidents involved UK organisations, including Co-op, Marks & Spencer, Harrods, the Legal Aid Agency and Pearson.

Key vulnerabilities exploited

  • GitLab personal access token (Pearson)
    A misconfigured or exposed token gave attackers source code access and credentials to internal services.
  • Infostealer malware (unknown credentials database)
    Though not tied to a single software flaw, this dataset was likely gathered silently over months from infected devices lacking endpoint protection.
  • AWS misconfiguration (TeleMessage)
    An unsecured S3-like store enabled unauthorised access to archived, plaintext versions of government messages.

List of data breaches and cyber attacks disclosed in May 2025

Disclosure date Organisation Country Sector Incident type Records affected
1 May Ascension Health USA Healthcare Third-party data breach (vulnerability exploit) 430,000 patients
1 May Barnstable County Sheriff’s Office USA Government (Law Enforcement) Insider data leak 101 employees
1 May Cobb County, Georgia USA Government (County) Ransomware (Qilin) Unknown (150 GB claimed)
1 May Synnovis (UK Labs) UK Healthcare (Laboratory) Ransomware (Qilin) Approximately 8,000 patients
1 May Commvault USA Tech (Data Management) Targeted cyber attack (zero-day exploit) Unknown
1 May Bartlesville Public Schools USA Education (K-12) Cyber attack (network outage) 6,000+ students
2 May Co-op UK Retail (Grocery) Ransomware (DragonForce) Up to 20 Million (claimed)
2 May Nova Scotia Power (Emera) Canada Energy (Utility) Cyber attack (unauthorised access) Unknown (customer data)
2 May Harrods UK Retail (Luxury) Cyber attack (attempted intrusion) Unknown
2 May Raw Dating App USA Technology (Dating App) Data leak (misconfiguration) 500,000+ users (Android installs)
2 May Magento e-Stores Global E-commerce (Retail) Supply-chain attack (Magecart) 500–1,000 stores
2 May Saskatoon Children’s Hospital Canada Healthcare Privacy breach (insider access) 314 patients
4 May TeleMessage (Signal clone) USA Technology (Encrypted Messaging) Hack (server takeover) Unknown (Gov’t comms data)
5 May Coweta County Schools USA Education (K-12) Cyber attack (suspected ransomware) 23,000 students
6 May Masimo USA Healthcare (MedTech) Cyber attack (operations disruption) Unknown
6 May iHeartMedia USA Media (Radio) Data breach (hackers undetected) Unknown (multi-state)
7 May Insight Partners USA Finance (Venture Capital) Cyber attack (social engineering; data theft) Unknown (employees & investors)
7 May South African Airways South Africa Transportation (Airline) Cyber attack (IT disruption) Unknown
8 May Pearson plc UK Education (EdTech) Cyberattack (token compromise; data theft) “Millions” of customers (legacy data)
8 May Japan FSA Japan Government (Financial Regulator) Account compromises (fraudulent trades) Unknown (≈$2 B funds moved)
8 May SogoTrade, Inc. USA Finance (Online Brokerage) Email account breach (phishing) 48,696 clients
10 May iClicker USA Education (EdTech) Website compromise (malware) Unknown
11 May Global Crossing Airlines USA Transportation (Airline) Cyber attack (hacktivist data theft) Unknown
12 May State of Alabama USA Government (State) “Cybersecurity event” (suspected ransomware) Unknown
13 May Marks & Spencer UK Retail (Department Store) Ransomware (DragonForce/Scattered Spider) Unknown (mass scale)
13 May Nucor Corporation USA Manufacturing (Steel) Cyber attack (IT disruption) Unknown
13 May Multiple Orgs – SAP NetWeaver Global Various (Energy, Water, Manufacturing, Gov’t) Nation‑state hacking (vulnerability exploits) 581 systems (across orgs)
14 May Coinbase USA Finance (Cryptocurrency) Insider breach + extortion 69,461 customers
14 May Australian Human Rights Commission Australia Government (Civil Rights) Data leak (misindexed documents) “Hundreds” of files
14 May Lecardo Clinic Russia Healthcare (Private Hospital) Cyber attack (hacktivist disruption) Unknown
19 May UK Legal Aid Agency UK Government (Legal Services) Cyber attack (data breach) Millions (15 yrs of applicants)
19 May Arla Foods Denmark (and Germany) Food & Agriculture Cyber attack (OT disruption) Unknown (production only)
20 May Kettering Health USA Healthcare (Hospital Network) Ransomware (Interlock) 67,000 patients
20 May Peter Green Chilled UK Logistics (Food Supply) Ransomware (Scattered Spider) Unknown (operations impact)
20 May Cellcom USA Telecom (Mobile Carrier) Cyber attack (service outage) Approximately 300,000 customers
22 May Coca-Cola USA/Middle East Beverage (Retail) Ransomware (Everest) 959 employees
22 May Open Credentials Database Global N/A (Multiple platforms) Data leak (unsecured server) 184,162,718 accounts
26 May MathWorks (MATLAB) USA Technology (Software) Ransomware attack (IT outage) Unknown
26 May Adidas Germany Retail (Apparel) Third-party breach (vendor hack) Unknown (customer count)
27 May City of Sheboygan, WI USA Government (City) Ransomware (Chort) 67,000 residents
28 May LexisNexis Risk Solutions USA Data analytics (Broker) Data breach (hacking) 364,000 individuals
28 May Victoria’s Secret USA Retail (Apparel) Cyber security incident (site offline) Unknown
29 May ConnectWise USA Technology (IT Software) Cyber attack (supply chain) Unknown (limited clients)
30 May ASVT ISP (Moscow) Russia Telecoms (Internet Service Provider) DDoS attack (service outage) Approximately 40,000 customers

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