Bug is not fixable

I get these as I have to submit security issues as bugs and then help whoever is in charge of the fixing find and implement a good solution. But apparently , nope . In some devs opinion , sqli issues are not fixable .

I also found one of these in the original Guild Wars , there were some places where texture would be applied wrong in the world and that enabled a few abuses . I submitted a complete bug report , way of replicating , how it's being used to abuse . Two weeks later support contacts me and tells me 'good find but sadly the issue is not fixable as we'd have to change the whole engine' . What the actual fuck kind of code did they use for texture mapping ?_?