If you try to open the following file
in ghostscript 9.06 it will fail with:
GPL Ghostscript 9.06 (2012-08-08)
Copyright (C) 2012 Artifex Software, Inc. All rights reserved.
This software comes with NO WARRANTY: see the file PUBLIC for details.
**** This file uses an unknown standard security handler revision: 6
Error: /undefined in pdf_check_password
%interp_exit .runexec2 --nostringval-- --nostringval-- --nostringval-- 2 %stopped_push --nostringval-- --nostringval-- --nostringval-- false 1 %stopped_push 1894 1 3 %oparray_pop 1893 1 3 %oparray_pop 1877 1 3 %oparray_pop --nostringval-- --nostringval-- --nostringval-- --nostringval-- false 1 %stopped_push --nostringval--
--dict:1158/1684(ro)(G)-- --dict:1/20(G)-- --dict:82/200(L)-- --dict:82/200(L)-- --dict:109/127(ro)(G)-- --dict:293/300(ro)(G)-- --dict:21/31(L)--
Current allocation mode is local
GPL Ghostscript 9.06: Unrecoverable error, exit code 1
the file can be opened in acrobat reader X (no password needed)
Created attachment 8903 [details]
I've confirmed that Ghostscript cannot read the attached file but that Acrobat Pro 10 and mu can.
*** Bug 694441 has been marked as a duplicate of this bug. ***
I just encountered this problem - mupdf can read it, but gs cannot; Adobe Reader 9.5.5 said a newer version is needed; xpdf cannot read it either. Indeed it says pdf 1.7.
This is likely to become a more common problem. My pdf is the monthly statement of a rather common credit card from a major bank in UK. Last month's pdf was still okay, so it looks like the bank just switched. (Ken/Chris may be seeing it first hand soon...).
Code has been added for this in commit c8673cb8209a9f294721fae7a1842fcd8940ecab
The revision 6 security handler is still not publicly available at this time, we are awaiting the published ISO 32000-2 specification which should contain it (due to be published in 2012....). The security handler is listed as 'extension level 8' and the most recent extension level document available is 3.
As a result we cannot guarantee that this code will work in all circumstances.