OpenJDK: imageio PNGImageReader failed to honor ignoreMetadata for iTXt and zTXt chunks (2D, 8166988)

It was discovered that the 2D component of OpenJDK performed parsing of iTXt and zTXt PNG image chunks even when configured to ignore metadata. An attacker able to make a Java application parse a specially crafted PNG image could cause the application to consume an excessive amount of memory...