Reading specially crafted serializable objects from an untrusted source may cause an infinite loop and denial of service
Any program on the JVM may read serialized objects via java.io.ObjectInputStream.readObject(). Reading serialized objects from an untrusted source is inherently unsafe (this affects any program running on any version of the JVM) and is a prerequisite for this vulnerability. Clojure classes that represent infinite seqs (Cycle, infinite Repeat, and Iterate) do not define hashCode() and use the parent ASeq.hashCode(), which walks the seq to compute the hash, yielding an infinite …