A flaw was found in the Apache Log4j logging library 2.x. when the logging configuration uses a non-default Pattern Layout with a Context Lookup. Attackers with control over Thread Context Map (MDC) input data can craft malicious input data that contains a recursive lookup and can cause Denial of Service.

In Spring Framework versions 5.2.0 - 5.2.8, 5.1.0 - 5.1.17, 5.0.0 - 5.0.18, 4.3.0 - 4.3.28, and older unsupported versions, the protections against RFD attacks from CVE-2015-5211 may be bypassed depending on the browser used through the use of a jsessionid path parameter.

Apache Ant could allow a remote authenticated attacker to bypass security restrictions, caused by an insecure temporary file flaw. By sending a specially-crafted request, an attacker could exploit this vulnerability to inject modified source files into the build process.