The encryption flaw that punctured the heart of the Internet this week underscores a weakness in Internet security: A good chunk of it is managed by four European coders and a former military consultant in Maryland.

Most of the 11-member team are volunteers; only one works full time. Their budget is less than $1 million a year. The Heartbleed bug, revealed Monday, was the product of a fluke introduced by a young German researcher.

...