Community.general: community.general: memcached cache plugin deserializes untrusted pickle data from memcached, enabling cache-poisoning remote code execution on the ansible controller

A flaw was found in the memcached cache plugin of the community.general Ansible
collection. Although its documentation states that records are stored in JSON
format, the plugin performs no explicit serialization and relies on
python-memcached, which pickles values on write and unpickles them on read.
Because memcached is unauthenticated and cache keys are predictable, an attacker
able to reach a network-exposed or shared memcached instance can write a crafted
pickle payload that is deserialized and executed on the Ansible controller when
the poisoned fact cache is next read, leading to remote code execution.