➜ Increase Default Value of the System Property jdk.jar.maxSignatureFileSize (JDK-8312489)

The system property, jdk.jar.maxSignatureFileSize, allows applications to control the maximum size of signature files in a signed JAR. Its default value has been increased from 8000000 bytes (8 MB) to 16000000 bytes (16 MB).

➜ -XshowSettings:locale Output Now Includes Tzdata Version (JDK-8305950)

The -XshowSettings launcher option has been enhanced to print the tzdata version configured with the JDK. The tzdata version is displayed as part of the locale showSettings option.

Example output using -X:showSettings:locale:

.....

Locale settings:
    default locale = English
    default display locale = English
    default format locale = English
    tzdata version = 2023c
    .....

➜ Removed SECOM Trust System's RootCA1 Root Certificate (JDK-8295894)

The following root certificate from SECOM Trust System has been removed from the cacerts keystore:

+ alias name "secomscrootca1 [jdk]"

  Distinguished Name: OU=Security Communication RootCA1, O=SECOM Trust.net, C=JP

➜ Added Certigna Root CA Certificate (JDK-8314960)

The following root certificate has been added to the cacerts truststore:

+ Certigna (Dhimyotis)

  + certignarootca
    DN: CN=Certigna Root CA, OU=0002 48146308100036, O=Dhimyotis, C=FR

➜ Debian JDK Installer Changes (JDK-8284854 (not public))

The installation directory of Oracle JDK Debian packages has changed. It was originally `/usr/lib/jvm/jdk-${FEATURE}`. With this release, it has been changed to `/usr/lib/jvm/jdk-${FEATURE}-oracle-${ARCH}`.

The Oracle JDK Debian package registers jexec as an interpreter for launching .jar files from the command line.

The Oracle JDK Debian package configures storage for Java Preferences API in the /etc/.java/.systemPrefs directory.

The Oracle JDK Debian package registers JDK commands with the update-alternatives command and supplies the /usr/lib/jvm/.jdk-${FEATURE}-oracle-${ARCH}.jinfo file for the update-java-alternatives command.

➜ Ignore Allow and Disallow Options for java.security.manager System Property (JDK-8301118)

In JDK 12, two new token options for the java.security.manager system property, "allow" and "disallow", were introduced.

Many applications and frameworks are designed to run on multiple JDKs. For those that enable the SecurityManager at runtime via System.setSecurityManager, they have to specify the "allow" option as of JDK 18 (see JDK-8203316). However, these applications would also prefer to use the same command line across multiple versions of the JDK, especially if it is not known what JDK version a user will use.

Currently, if these options are specified in JDK 12 or earlier, the runtime attempts to load a SecurityManager implementation with the classname "allow" or "disallow", which results in a Could not create SecurityManager Error and the application will not start up.

From this release onward, the "allow" and "disallow" options for the java.security.manager system property will be ignored.

➜ The Default TLS Diffie-Hellman Group Size Has Been Increased from 1024-bit to 2048-bit (JDK-8301700)

The JDK implementation of TLS 1.2 now uses a default Diffie Hellman keysize of 2048 bits when a TLS_DHE cipher suite is negotiated and either the client or server does not support FFDHE, which can negotiate a stronger keysize. The JDK TLS implementation supports FFDHE and it is enabled by default.

As a workaround, users can revert to the previous size by setting the jdk.tls.ephemeralDHKeySize system property to 1024 (at their own risk).

This change does not affect TLS 1.3 as the minimum DH group size is already 2048 bits.

➜ Use Server Cipher Suites Preference by Default (JDK-8168261)

For TLS connections, the cipher suite selection, by default, is updated to use the server cipher suites preference. Applications can configure the behavior by using the SSLParameters.setUseCipherSuitesOrder​() method.