Netcraft confirms many U.S. Department of Defense websites, including a remote access service used by the Missile Defense Agency, are more vulnerable to man-in-the-middle attacks than most consumer websites. The weaker than previously-thought SHA-1 algorithm is the main culprit, with the DoD today being the most prolific user of SHA-1 signed SSL certificates, even though NIST banned new use of this signature algorithm two years ago. Most of the vulnerable certificates to be issued recently are used by .mil websites, which are operated by agencies, services and divisions of the DoD. All of these sites are consequently vulnerable to attack by enemy governments and criminals who can stump up enough cash ($75,000) to crack the certificates.

