When processing user provided XML documents, the Spring Framework 4.0.0 to 4.0.4, 3.0.0 to 3.2.8, and possibly earlier unsupported versions did not disable by default the resolution of URI references in a DTD declaration. This enabled an XXE attack.

Spring Framework 3.0.0 through 3.0.5, Spring Security 3.0.0 through 3.0.5 and 2.0.0 through 2.0.6, and possibly other versions deserialize objects from untrusted sources, which allows remote attackers to bypass intended security restrictions and execute untrusted code by (1) serializing a java.lang.Proxy instance and using InvocationHandler, or (2) accessing internal AOP interfaces, as demonstrated using deserialization of a DefaultListableBeanFactory instance to execute arbitrary commands via the java.lang.Runtime class.