A flaw was found in the way the JSSE component in OpenJDK performed X.509 certificate identify verification when establishing TLS/SSL connection to a host identified using IP address. In certain cases, it would incorrectly use a host name obtained after performing reverse DNS lookup of the specified IP address rather than the original IP address for the identity check, possibly leading to having a certificate issued for different identity to be accepted as valid.

This issue is know to affect cases when SSLSocketFactory.createSocket() is called with certain InetAddress instances. It is not known to affect cases when target host IP is passed to createSocket() as string, or when IP is used in URL used for HttpsURLConnection.

With this patch, reverse DNS lookup is no longer performed. The fix also adds new system property jdk.tls.trustNameService that can be used to allow the DNS lookup to be performed and hence have its result used during identity check.

A flaw was found in the way the Libraries component of OpenJDK verified OCSP (Online Certificate Status Protocol) response. An OCSP response with no nextUpdate date specified was incorrectly handled as having unlimited validity. This could allow a Java application to accept a revoked X.509 certificate as valid if it was presented with an OCSP response generated before certificate revocation.

It was discovered that the JCE (Java Cryptography Extension) component in OpenJDK failed to use constant time comparisons in multiple cases. An attacker could possibly use these flaws to disclose sensitive information by measuring time used to perform operations using these non-constant time comparisons.

It was discovered that the DnsClient client class in the JNDI (Java Naming and Directory Interface) component in OpenJDK failed to properly remove information about an outgoing DNS request from the list of outstanding DNS requests when certain errors occurred during DNS resolution. An attacker able to trigger such DNS errors could cause a Java application using JNDI to consume memory and possibly block further DNS resolution (after exhausting all DNS transaction ids).