New in release OpenJDK 8u352 (2022-10-18)

• Release announcement
• Full release notes

Security Fixes

• JDK-8282252: Improve BigInteger/Decimal validation
• JDK-8285662: Better permission resolution
• JDK-8286511: Improve macro allocation
• JDK-8286519: Better memory handling
• JDK-8286526, CVE-2022-21619: Improve NTLM support
• JDK-8286533, CVE-2022-21626: Key X509 usages
• JDK-8286910, CVE-2022-21624: Improve JNDI lookups
• JDK-8286918, CVE-2022-21628: Better HttpServer service
• JDK-8288508: Enhance ECDSA usage

Major Changes

JDK-8201793: (ref) Reference object should not support cloning

java.lang.ref.Reference::clone method always throws CloneNotSupportedException. Reference objects cannot be meaningfully cloned. To create a new Reference object, call the constructor to create a Reference object with the same referent and reference queue instead.

JDK-8175797: (ref) Reference::enqueue method should clear the reference object before enqueuing

java.lang.ref.Reference.enqueue method clears the reference object before it is added to the registered queue. When the enqueue method is called, the reference object is cleared and get() method will return null in OpenJDK 8u352.

Typically when a reference object is enqueued, it is expected that the reference object is cleared explicitly via the clear method to avoid memory leak because its referent is no longer referenced. In other words the get method is expected not to be called in common cases once the enqueuemethod is called. In the case when the get method from an enqueued reference object and existing code attempts to access members of the referent, NullPointerException may be thrown. Such code will need to be updated.

JDK-8071507: (ref) Clear phantom reference as soft and weak references do

This enhancement changes phantom references to be automatically cleared by the garbage collector as soft and weak references.

An object becomes phantom reachable after it has been finalized. This change may cause the phantom reachable objects to be GC'ed earlier - previously the referent is kept alive until PhantomReference objects are GC'ed or cleared by the application. This potential behavioral change might only impact existing code that would depend on PhantomReference being enqueued rather than when the referent be freed from the heap.

JDK-8286918: Better HttpServer service

The HttpServer can be optionally configured with a maximum connection limit by setting the jdk.httpserver.maxConnections system property. A value of 0 or a negative integer is ignored and considered to represent no connection limit. In the case of a positive integer value, any newly accepted connections will be first checked against the current count of established connections and, if the configured limit has been reached, then the newly accepted connection will be closed immediately.

JDK-8282859: Enable TLSv1.3 by Default on JDK 8 for Client Roles

The TLSv1.3 implementation is now enabled by default for client roles in 8u352. It has been enabled by default for server roles since 8u272.

Note that TLS 1.3 is not directly compatible with previous versions. Enabling it on the client may introduce compatibility issues on either the server or the client side. Here are some more details on potential compatibility issues that you should be aware of:

• TLS 1.3 uses a half-close policy, while TLS 1.2 and prior versions use a duplex-close policy. For applications that depend on the duplex-close policy, there may be compatibility issues when upgrading to TLS 1.3.

• The signature_algorithms_cert extension requires that pre-defined signature algorithms are used for certificate authentication. In practice, however, an application may use non-supported signature algorithms.

• The DSA signature algorithm is not supported in TLS 1.3. If a server is configured to only use DSA certificates, it cannot upgrade to TLS 1.3.

• The supported cipher suites for TLS 1.3 are not the same as TLS 1.2 and prior versions. If an application hard-codes cipher suites which are no longer supported, it may not be able to use TLS 1.3 without modifying the application code.

• The TLS 1.3 session resumption and key update behaviors are different from TLS 1.2 and prior versions. The compatibility should be minimal, but it could be a risk if an application depends on the handshake details of the TLS protocols.

The TLS 1.3 protocol can be disabled by using the jdk.tls.client.protocols system property:

java -Djdk.tls.client.protocols="TLSv1.2" ...

Alternatively, an application can explicitly set the enabled protocols with the javax.net.ssl APIs e.g.

sslSocket.setEnabledProtocols(new String[] {"TLSv1.2"});

or:

SSLParameters params = sslSocket.getSSLParameters();
params.setProtocols(new String[] {"TLSv1.2"});
sslSocket.setSSLParameters(params);