Algorithm::UrataniTakeda versions from 0.1.5 before 0.1.7 for Perl allow memory exhaustion via a never-cleared failure shift cache in search

Algorithm::UrataniTakeda versions from 0.1.5 before 0.1.7 for Perl allow memory exhaustion via a never-cleared failure shift cache in search.

The failure shift is cached for each pair of trie state and text character in a field of the matcher object, and nothing clears it. A character not seen before at a given state adds an entry that lasts for the life of the matcher.

An attacker who can submit text with many distinct characters to a long-lived matcher can grow its memory with each search.