Cookies, the files that websites create in browsers to remember logged-in users and track other information about them, could be abused by attackers to extract sensitive information from encrypted HTTPS connections.

On the eve of a significant agreement between the United States and China on trade and information security, the head of the National Security Agency cautioned that the two superpowers must develop a set of norms that would curb cyber-espionage and theft of intellectual property from U.S. firms.