jsoup through 1.23.2, fixed in commit 862ba2f, contains an uncontrolled resource consumption vulnerability in XmlTreeBuilder that allows remote attackers to exhaust JVM heap memory by supplying a deeply nested XML document with uniquely-namespaced elements. The builder copies the entire inherited namespace map on every start element, causing quadratic time and memory complexity, which attackers can exploit to trigger an OutOfMemoryError and terminate the application.

jsoup versions through 1.23.2 contain an uncontrolled resource consumption vulnerability in the XmlTreeBuilder component. Remote attackers can exploit this by supplying a deeply nested XML document with uniquely-namespaced elements. The root cause is that the builder copies the entire inherited namespace map on every start element encountered, resulting in quadratic time and memory complexity. This behavior can be weaponized to exhaust JVM heap memory, triggering an OutOfMemoryError and effectively terminating the application. The vulnerability is fixed in commit 862ba2f. No special authentication or privileges appear to be required for exploitation, making it accessible to remote unauthenticated attackers. The fix is tracked in GitHub pull request #2556.