Learn / Famous incidents explained
Famous incidents explained
The landmark security events of the last four decades, what actually happened, and the lessons defenders still use today.
Every security practice you follow today was learned the hard way by someone. These case studies explain what happened in each event, how it worked at a high level, the impact, and what it means for you. They stick to established public facts and avoid speculation about who was behind them where that is contested.
IncidentHeartbleed (2014)A tiny bug in the OpenSSL encryption library let anyone read chunks of server memory, exposing passwords and private keys across the web.IncidentLog4Shell (2021)A flaw in a tiny, free logging library turned out to be hiding inside millions of apps and devices. Why Log4Shell was called one of the most serious vulnerabilities in a decade, and what it taught the software world.
IncidentThe Colonial Pipeline ransomware attack (2021)A ransomware attack on business IT systems led a major fuel pipeline operator to halt operations for several days as a precaution.IncidentThe CrowdStrike outage (2024)Not a hack at all. A faulty security software update crashed about 8.5 million Windows computers on July 19, 2024, grounding flights and disrupting hospitals. What went wrong and why resilience is part of security.
IncidentThe Equifax breach (2017)An unpatched web application flaw exposed Social Security numbers and other personal data of about 147 million people.IncidentThe ILOVEYOU worm (2000)A love-letter email that tricked millions of people into running a script, and showed how social engineering beats technical defenses.IncidentThe MOVEit breaches (2023)A single flaw in a popular file-transfer product let one criminal group steal data from thousands of organizations at once. A textbook case of supply-chain risk and extortion without encryption.
IncidentThe Mirai botnet (2016)Hundreds of thousands of cameras and routers with factory-default passwords were hijacked to knock major websites offline.IncidentThe Morris worm (1988)A graduate student's experiment that spread out of control across the early internet and led to the first computer emergency response team.
IncidentThe Target breach (2013)Attackers entered through a heating contractor's login and planted card-stealing malware on checkout terminals during the holiday rush.
IncidentThe Twitter account hijack (2020)Phone-based social engineering of employees gave attackers access to internal tools and some of the most-followed accounts on the platform.
IncidentThe Yahoo breaches (2013 and 2014)The largest known data breach of its era touched all three billion Yahoo accounts, and came to light years after it happened.
IncidentWannaCry ransomware (2017)A ransomware worm used a Windows file-sharing flaw that had been patched two months earlier to spread to hundreds of thousands of computers in a day.