Buffer
Overflow Intro. ©2002, Jedidiah R. Crandall, Susan L. Gerhart, Jan G.
Hogle.
http://sfsecurity.pr.erau.edu
Patty knows that a buffer
overflow will ovewrite the return point to go to
her program
68, the ASCII
representation for a “D”, is put in mailbox #78. But mailbox #78 was being used
to store the return address!
Now when Norman is finished
with the GetLastName() subroutine, he will read a
68 as the return address instead of the real return address.
He’ll then begin executing
instructions at mailbox #68, which is Patty’s instructions to
steal Norman and make him do what Patty wants instead of what
Alice wants (Patty’s hijacking subroutine, if treated as
ASCII, just so happens to spell out SOLZHENGRA).