The PlRPC module, possibly 0.2020 and earlier, for Perl uses the Storable module, which allows remote attackers to execute arbitrary code via a crafted request, which is not properly handled when it is deserialized.
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.