Global systems administrators scramble to secure networks against widespread certificate flaw

A major security flaw in eight intermediate CA certificates has left billions of older devices and software installations vulnerable to impersonation attacks. This flaw has forced systems administrators worldwide to update untold amounts of machines and software, as attackers could now impersonate any domain and make malware appear to come from legitimate sources. An attacker anywhere in the path of a network connection could intercept it and pretend to be any website, like apple.com or bankofamerica.com, without the operating system or software being aware of the deception. With code signing certificates, downloaded applications could appear completely legitimate from major companies like Microsoft or Google. The way software checks a certificate's legitimacy is by verifying its chain, starting from the certificate issued by an intermediate CA and going up to root certificates. In this week's event, Indian CA firm eMudhra issued six TLS and two code-signing intermediate certificates with easily guessable keys. These certificates needed to be updated, with their chains being revoked and their keys hard-coded into rejection lists. Recent versions of Chrome, Brave, Firefox, and Safari include a feature called Certificate Transparency, which logs all certificate issuances and blocks any that aren't mentioned. Google reports that no certificates signed by the six affected intermediate CAs were logged, so if regular web browsing is all that was done, users may be safe, but updates are still needed. The sheer amount of machines and software that need updating includes PCs, servers, phones, tablets, routers, web browsers, and many more, including older devices like smart and IoT appliances. The private keys for the affected certificates were only 1 byte long, making them trivial to brute-force, and the cause of this error is still under investigation. The flaw has already caused significant disruption, and systems administrators are working tirelessly to secure networks before further attacks can occur.