CVE識別番号: CVE-2015-4000
  情報公開日: 8 14, 2015

  概要

The TLS protocol 1.2 and earlier, when a DHE_EXPORT ciphersuite is enabled on a server but not on a client, does not properly convey a DHE_EXPORT choice. This allows man-in-the-middle attackers to conduct cipher-downgrade attacks by rewriting a ClientHello with DHE replaced by DHE_EXPORT and then rewriting a ServerHello with DHE_EXPORT replaced by DHE, which could then result in an attacker being able to monitor encrypted communications by being able to decrypt them. This is known as the "Logjam" vulnerability.

  対応方法