U.S. cybersecurity officials fear potentially devastating cyberattacks following discovery of a flaw in the widely-used Java-based software Log4j, CNN reports. Companies use Log4j to keep records of users' activities in order to perform security reviews. The flaw risks data breaches to user data at any company employing it on their servers. U.S. Cybersecurity and Infrastructure Security Agency Director Jen Easterly considers the flaw "one of the most serious" the U.S. has seen and expects it "to be widely exploited by sophisticated actors."