A lack of corporate awareness about the potential abuse of digital certificates has security advocates fighting an uphill battle in the effort to close authentication loopholes that are being routinely exploited by hackers, one security specialist has warned.
Spoofing or theft of legitimate digital certificates in recent years has increased dramatically, gaining some awareness after the notorious Stuxnet worm used a hijacked VeriSign digital-certificate to slip into victim networks. Subsequent attacks – for example, the DigiNotar and Comodo, and others have strengthened concerns that digital-certificate fraud is becoming a mainstream tool by which malware authors can rapidly infect target networks.
Promulgating change throughout the business community is difficult because certificate revocation lists (CRLs) are often ignored by many operating systems. Even more problematic, warns Venafi CEO Jeff Hudson, is the spread of certificates across mobile devices – which heavily rely on the certificates for all kinds of authentication but in doing so significantly increase the need for proactive security management.
“Every single phone has certificates on it to authenticate,” Hudson told CSO Australia. “They expire, and people can’t keep track of them. The bad guys have figured out that the large organisations in the world are not paying attention to these certificates, which are a trust instrument. They love to attack where you’re not looking, and where you can’t remediate.”
A certificate problem took Microsoft’s Azure cloud-computing platform offline for more than a day in February, simply because of a Microsoft failure to renew an important secure sockets layer (SSL) encryption certificate.
The incident led to one affected party launching a free service, CertAlert.me, which watches the expiration dates of certificates and notifies potentially affected parties well before they repeat Microsoft’s Azure blue.
If certificate-management accidents can have such a dramatic effect on a high-profile company like Microsoft, the implications for smaller organisations are significant. Poor executive understanding of the workings of digital certificates increase the challenge, Hudson says, because it can be hard for CSOs to introduce adequate protections on the certificates – which often linger long after the employees they pertain to have left the company.
One company, which Venafi audited for digital-certificate compliance, thought it had 5000 digital certificates issued at the time; however, a comprehensive audit of its certificates showed 20,000 certificates were currently allowing access to company systems.
“Companies have those certificates out there that can cause them damage, and nobody knows why,” Hudson said. “Folks are supposed to hold those certificates all the way, and once you have a trusted channel, that’s the way the world is supposed to work. But if someone steals or forges one, and you’ve brought it inside and can set up a trusted certificate channel, you’ve got trouble.”
Identifying and removing the excess certificates took that company six months, but those that make no effort to do so are leaving themselves exposed to potentially even worse problems.
With certificate-based cloud computing looming on the horizon and ever more-valuable resources being managed based on an organisation’s trust in mobile certificates, Hudson warns, the potential risks of poor certificate management continue to threaten the integrity of corporate systems.
“The technical architecture of certificates works perfectly,” he says. “The problem is that people haven’t invested in protecting it – because they don’t understand it.”