"first they ignore you, then they threaten to sue you, then they deny the vulnerability, then you p0wn them" -- with apologies to Mahatma Gandhi
archimede:~$ file pocorgtfo05.pdf 
pocorgtfo05.pdf: ISO 9660 CD-ROM filesystem data 'TetrangOS                      ' (bootable)

and

archimede:~$ unzip -v pocorgtfo05.pdf 
Archive:  pocorgtfo05.pdf
warning [pocorgtfo05.pdf]:  26368859 extra bytes at beginning or within zipfile
  (attempting to process anyway)
 Length   Method    Size  Ratio   Date   Time   CRC-32    Name
--------  ------  ------- -----   ----   ----   ------    ----
       0  Stored        0   0%  08-04-14 21:11  00000000  PEXternalizer/
       0  Stored        0   0%  08-04-14 21:11  00000000  PEXternalizer/gerbers/
   36757  Defl:X     8364  77%  08-04-14 21:11  8951ef3a  PEXternalizer/gerbers/mPEXternalizer.GBL
     350  Defl:X      178  49%  08-04-14 21:11  41ef7268  PEXternalizer/gerbers/mPEXternalizer.XLN
   43198  Defl:X     9972  77%  08-04-14 21:11  1d07892a  PEXternalizer/gerbers/mPEXternalizer.GTL
  126902  Defl:X    28569  78%  08-04-14 21:11  9e23dd0a  PEXternalizer/gerbers/PEXternalizer.GTL
   10607  Defl:X     1999  81%  08-04-14 21:11  1362f6a4  PEXternalizer/gerbers/mPEXternalizer.GTS
    1079  Defl:X      394  64%  08-04-14 21:11  2b2fd9f2  PEXternalizer/gerbers/PEXternalizer.XLN
   20909  Defl:X     4710  78%  08-04-14 21:11  ea04d9a4  PEXternalizer/gerbers/mPEXternalizer.GBO
   45783  Defl:X     9521  79%  08-04-14 21:11  fa67abdf  PEXternalizer/gerbers/PEXternalizer.GBO
   35428  Defl:X     7655  78%  08-04-14 21:11  a9df2250  PEXternalizer/gerbers/PEXternalizer.GTO
    1268  Defl:X      406  68%  08-04-14 21:11  72fecc3a  PEXternalizer/gerbers/mPEXternalizer.GBS
    9731  Defl:X     2442  75%  08-04-14 21:11  ab8908e0  PEXternalizer/gerbers/mPEXternalizer.GKO
  128653  Defl:X    29251  77%  08-04-14 21:11  40fe72f8  PEXternalizer/gerbers/PEXternalizer.GBL
   11186  Defl:X     2061  82%  08-04-14 21:11  c540d525  PEXternalizer/gerbers/PEXternalizer.GBS
    9012  Defl:X     2246  75%  08-04-14 21:11  b25e9619  PEXternalizer/gerbers/PEXternalizer.GKO
   30759  Defl:X     6634  78%  08-04-14 21:11  2ffd2bb9  PEXternalizer/gerbers/mPEXternalizer.GTO
   18201  Defl:X     3318  82%  08-04-14 21:11  73340665  PEXternalizer/gerbers/PEXternalizer.GTS
   18026  Defl:X     6802  62%  08-04-14 21:11  314a1dd2  PEXternalizer/LICENSE
       0  Stored        0   0%  08-04-14 21:11  00000000  PEXternalizer/eagle/
  118946  Defl:X    11313  91%  08-04-14 21:11  a1811f8e  PEXternalizer/eagle/PEXternalizer.sch
   67047  Defl:X     9735  86%  08-04-14 21:11  9a64483a  PEXternalizer/eagle/PEXternalizer.brd
   59982  Defl:X     8815  85%  08-04-14 21:11  a20ed85f  PEXternalizer/eagle/mPEXternalizer.brd
   54806  Defl:X     6088  89%  08-04-14 21:11  c7201662  PEXternalizer/eagle/mPEXternalizer.sch
     890  Defl:X      460  48%  08-04-14 21:11  4079216b  PEXternalizer/PEXternalizer-BOM.csv
       0  Stored        0   0%  08-04-14 21:11  00000000  PEXternalizer/eagle-support/
   75865  Defl:X     7422  90%  08-04-14 21:11  21e5cb30  PEXternalizer/eagle-support/con-pci_express%28pci-e%29.lbr
  293800  Defl:X    32560  89%  08-04-14 21:11  683f0417  PEXternalizer/eagle-support/securinghardware.lbr
   42631  Defl:X     4062  91%  08-04-14 21:11  f9489239  PEXternalizer/eagle-support/con-heo.mini_pci_express.lbr
    1844  Defl:X      991  46%  08-04-14 21:11  ef785144  PEXternalizer/README.md
       0  Stored        0   0%  08-04-14 21:11  00000000  collision/
  447780  Defl:X   248722  45%  08-04-14 21:11  1d2cf7e7  collision/mbr_shell_rar1.pdf
  110809  Defl:X    50821  54%  08-04-14 21:11  b7e897e3  collision/jpg-rar0.jpg
    2347  Defl:X      945  60%  08-04-14 21:11  8fa25759  collision/msha1.py
     354  Defl:X      167  53%  08-04-14 21:11  fa48f512  collision/readme.txt
  447780  Defl:X   248722  45%  08-04-14 21:11  dbf86217  collision/mbr_shell_rar0.pdf
    2560  Defl:X      997  61%  08-04-14 21:11  c789f50e  collision/make_collision.py
  110809  Defl:X    50823  54%  08-04-14 21:11  fa6f5705  collision/jpg-rar1.jpg
    1294  Defl:X      604  53%  08-04-14 21:11  9899e045  lazy.c
     549  Defl:X      278  49%  08-04-14 21:11  677cef1f  manulmascot.txt
    7873  Defl:X     2737  65%  08-04-14 21:11  4cf0df95  mpbs.asm
    2285  Defl:X      975  57%  08-04-14 21:11  d6685e2a  rosetta-rick.swf
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/utils/
    1340  Defl:X      537  60%  08-04-14 21:11  8e5b076b  rosettaflash/utils/utils.go
   18092  Defl:X     6806  62%  08-04-14 21:11  4e46f4a1  rosettaflash/LICENSE
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/zlibStream/
   10608  Defl:X     2446  77%  08-04-14 21:11  1425ab06  rosettaflash/zlibStream/zlibStream.go
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/flashFile/
     973  Defl:X      389  60%  08-04-14 21:11  431e95ba  rosettaflash/flashFile/flashFile.go
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/huffman/
    9786  Defl:X     1906  81%  08-04-14 21:11  9f69b64f  rosettaflash/huffman/huffman.go
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/adler32_fuzzer/
    1306  Defl:X      536  59%  08-04-14 21:11  64b13546  rosettaflash/adler32_fuzzer/adler32_fuzzer.go
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/adler32_mod/
    1465  Defl:X      648  56%  08-04-14 21:11  c111e13a  rosettaflash/adler32_mod/adler32_mod.go
     240  Defl:X      186  23%  08-04-14 21:11  017e3177  rosettaflash/CREDITS
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/charset/
    1139  Defl:X      440  61%  08-04-14 21:11  6da2eaae  rosettaflash/charset/charset.go
       0  Stored        0   0%  08-04-14 21:11  00000000  rosettaflash/PoC/
    1158  Defl:X      517  55%  08-04-14 21:11  61d7c149  rosettaflash/PoC/eval_load-ascii.swf
     148  Defl:X      104  30%  08-04-14 21:11  b8d6cec9  rosettaflash/PoC/check_alphanum.py
     248  Defl:X      144  42%  08-04-14 21:11  72266fc7  rosettaflash/PoC/eval_load.as
     377  Defl:X      286  24%  08-04-14 21:11  813608cc  rosettaflash/PoC/rickroll.swf
     179  Defl:X      136  24%  08-04-14 21:11  6d8363f1  rosettaflash/PoC/rickroll.as
     393  Defl:X      220  44%  08-04-14 21:11  b16dd2e2  rosettaflash/PoC/UniversalExfiltrator.as
    1231  Defl:X      554  55%  08-04-14 21:11  a18a5d35  rosettaflash/PoC/rickroll-ascii.swf
    1629  Defl:X      639  61%  08-04-14 21:11  5218837d  rosettaflash/PoC/UniversalExfiltrator-ascii.swf
     541  Defl:X      360  34%  08-04-14 21:11  0c957a2b  rosettaflash/PoC/UniversalExfiltrator.swf
     294  Defl:X      209  29%  08-04-14 21:11  6de9a584  rosettaflash/.gitignore
    1085  Defl:X      570  48%  08-04-14 21:11  8e98d963  rosettaflash/README.md
    2796  Defl:X     1137  59%  08-04-14 21:11  decc6797  rosettaflash/rosettaflash.go
     962  Defl:X      468  51%  08-04-14 21:11  09e790ac  style.txt
56807352  Defl:X 56275027   1%  08-04-14 21:11  be2ccd2d  pocorgtfo04.pdf
--------          -------  ---                            -------
59261442         57106024   4%                            74 files

and, by now, you do recall that within 0x04 lies other interesting material, do you not?

As usual there is more...

wittgenstein:~$ sudo mount -o ro -t iso9660 pocorgtfo05.pdf /mnt
[sudo] password for arrigo: 
wittgenstein:~$ cd /mnt/
wittgenstein:/mnt$ ls -l
total 1443
-r-xr-xr-x 1 root root    2048 Jul 17 12:00 boot.cat
-r-xr-xr-x 1 root root      51 Jul 17 12:00 readme.txt
-r-xr-xr-x 1 root root 1474560 Jul 17 12:00 tetrangl.img

That worked!

wittgenstein:/mnt$ cat readme.txt 
Never gonna give you up!
Never gonna let you down!
wittegenstein:/mnt$ file *
boot.cat:     FoxPro FPT, blocks size 0, next free block index 16777216
readme.txt:   ASCII text
tetrangl.img: x86 boot sector

So, what should you do next? Well, how about a little emulation...

archimede:~$ qemu-system-i386 -cdrom pocorgtfo05.pdf
PoC||GTFO 0x05 booting under QEmu into Tetris