Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0, 2.12.3, and 2.3.1.

Apache Ant 1.1 to 1.9.14 and 1.10.0 to 1.10.7 uses the default temporary directory identified by the Java system property java.io.tmpdir for several tasks and may thus leak sensitive information. The fixcrlf and replaceregexp tasks also copy files from the temporary directory back into the build tree allowing an attacker to inject modified source files into the build process.