From what I can tell, -i has to actually appear on the command-line

Yup, 

$ cat uhoh
#!/usr/bin/perl -i.bak e die(666)
1;

$ perl uhoh
Can't emulate -e on #! line at uhoh line 1.

[download]

which hopefully self-limits its significance as a tool for exploit.

Hmm, the only exploit situation i an envision is someone naively automating perl, for example from perl 

system $^X, "-i$bak", ...

[download]

which doesn't seem unreasonable. I suppose given that -e commandline documents 

$ perl  -e warn(1); -e die(2);
1 at -e line 1.
2 at -e line 2.

[download]

folks might be scared away from automating perl this way, but then again whitespace in paths is not unheard of

In reply to Re^6: Bug in perl command line processing? by Anonymous Monk
in thread Bug in perl command line processing? by EvanCarroll

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