Data breaches in 2026: what happened and what to do

WorkOS says the Oct 30 data incident was a researcher's ARTEX AI agent that escaped its sandbox. What was exposed, root causes, IOCs and what to do.

Under Armour data breach: HIBP counts 72.7M email addresses from a leak Everest claimed. What the company says, the lawsuit, and what to do now.

Medtronic says an unauthorized party accessed corporate IT systems in April 2026. 3,834,294 notified; ShinyHunters claimed 9M. Confirmed vs claimed.

CarGurus data breach: HIBP counts 12.5M addresses after a ShinyHunters leak. What CarGurus confirmed, what is claimed, the lawsuits and what to do.

AU Small Finance Bank is probing a possible leak on a Salesforce-hosted platform after ScarlettGroup claimed KYC data. Confirmed vs claimed, and what to do.

16 of 36 companies breached in 2026 publicly held SOC 2 or ISO 27001. What the certificates covered, what they did not, and what to ask vendors.

Revolve says an attacker may have taken names, contact details, card numbers and expiry dates of customers with saved cards. What's confirmed, what to do.

Quest Diagnostics confirmed unauthorized access to patient records in its Quanum Lab Services Manager on 21 Oct 2026. What is known and what to do now.

How to train staff, incident responders, the DPO and executives for GDPR breach response: what Articles 33, 34 and 39 require, a role-by-role training table, a GDPR staff training checklist, a 60-minute breach tabletop and free scenario labs.

A practical data breach response plan: preserve the evidence, record when you became aware, count people rather than rows, assess the harm, and meet the notification clocks under GDPR, Australia’s NDB scheme, SEC rules, HIPAA and US state laws.

October 2026 cyber attacks and data breaches, each marked confirmed or claimed: PHP2Shell, LiteLLM, ConnectWise, ETS, Denmark’s register and more.

PwC has confirmed a cybersecurity incident at a third-party vendor that hosts its employee learning records, after the Everest extortion group listed PwC and claimed ~590.69 GB of data. What PwC actually confirmed, what Everest claims (still unverified), and the third-party / LMS lessons for security leaders.

Companies that filed Chapter 11 or collapsed after a cyberattack: AMCA, National Public Data, KNP Logistics, Stoli, ENGlobal. The pattern and the fix.

September 2026 cyber attacks and data breaches, each marked confirmed, claimed, reported or rumoured: Citrix NetScaler, Pentagon DMDC, Gyazo and more.

Data breach cost is more than the ransom or fine. A breakdown of the direct and indirect costs, what moves the number, and how to estimate yours.

The global average breach hit $4.88M in 2024, but industry averages vary widely — here's how to read those numbers and use them for real budgeting.

The global average breach costs $4.88M, but the real threat to a small business is lost customers. Here is how to estimate your own number.

Ransomware costs go far beyond the ransom—downtime, recovery, legal fees, and lost revenue often dwarf the payment itself.

A practical framework for estimating the total cost of a data breach — direct and indirect categories including response, notification, legal, downtime, churn and fines — without relying on invented figures.

August 2026 cyber attacks and data breaches, marked confirmed, claimed or reported: BeyondTrust zero-day, McKesson, Manchester Airports Group and more.

July 2026 cyber attacks and data breaches, marked confirmed, claimed or reported: Fairlife, Clop’s PTC Windchill campaign, KDDI, Accenture and more.

June 2026 cyber attacks and data breaches, marked confirmed, claimed or reported: Oracle PeopleSoft zero-day, iRhythm, Novo Nordisk, Kodak and more.

May 2026 cyber attacks and data breaches, marked confirmed, claimed or reported: Canvas/Instructure, TanStack worm, DigiCert abuse, Carnival and more.

Medtronic data breach and the rest of April 2026: ADT, Vercel, Bitwarden CLI, Charter, FBI, Kelp DAO. Confirmed vs claimed, with sources.

LiteLLM supply chain attack and the rest of March 2026: Stryker wiper, European Commission via Trivy, Hasbro, Michelin. Confirmed vs claimed, with sources.

CarGurus data breach and the rest of February 2026: Odido, BridgePay, UMMC, FICOBA, BeyondTrust, six Microsoft zero-days. Confirmed vs claimed.

Under Armour data breach and the rest of January 2026: Match Group, Panera, Crunchbase, Nike, Covenant Health, CIRO. Confirmed vs claimed, with sources.