The paper "Insertion, Evasion, and Denial of Service: Eluding Network Intrusion Detection" [REF-428] shows that OSes varied widely in how they manage unusual packets, which made it difficult or impossible for intrusion detection systems to properly detect certain attacker manipulations that took advantage of these OS differences.
Null characters have different interpretations in Perl and C, which have security consequences when Perl invokes C functions. Similar problems have been reported in ASP [REF-429] and PHP.