Daniel Kaminsky Obituary: Daniel Kaminsky, a security scientist known for his revelation of a key defect in the texture of the web, passed on Friday at his home in San Francisco. He was 42.

His auntie, Dr. Toby Maurer, said the reason was diabetes ketoacidosis, a genuine diabetic condition that prompted his successive hospitalization as of late.

In 2008, Mr. Kaminsky was broadly hailed as an advanced Paul Revere after he tracked down a genuine imperfection in the web’s essential pipes that could permit talented coders to assume control over sites, redirect bank qualifications or even shut down the web. Mr. Kaminsky alarmed the Department of Homeland Security, chiefs at Microsoft and Cisco, and other web security specialists to the issue and aided initiate a fix.