-
Notifications
You must be signed in to change notification settings - Fork 18
/
suri-suspicious-pdf.lua
419 lines (401 loc) · 14.8 KB
/
suri-suspicious-pdf.lua
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
--[[
#*************************************************************
# Copyright (c) 2003-2013, Emerging Threats
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
# following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice, this list of conditions and the following
# disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
# following disclaimer in the documentation and/or other materials provided with the distribution.
# * Neither the name of the nor the names of its contributors may be used to endorse or promote products derived
# from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS AS IS AND ANY EXPRESS OR IMPLIED WARRANTIES,
# INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
#*************************************************************
Detection for suspicious PDF files. Currently only supports /FlateDecode requires luazlib module.
#lua-zlib
https://github.com/brimworks/lua-zlib
#lua-apr
sudo apt-get install lua-apr lua-apr-dev
This lua script can be run standalone and verbosely on a PDF file with
echo "run()" | lua -i <script name> <pdf file>
Chris Wakelin
Will Metcalf
--]]
local lz = require 'zlib'
require 'struct'
local apr = require 'apr.core'
function init (args)
local needs = {}
needs["http.response_body"] = tostring(true)
return needs
end
function cve_2013_2729(xfa,verbose)
if string.find(xfa,"<image[^>]*>[\n%s\r]-Qk[A-Za-z0-9%+%/\n%s\r]-AAL/AAAC/wAAAv8AAAL/AAAC/wAAAv8AAAL/AAAC/wAAAv8AAAL/AAAC") ~= nil then
if verbose == 1 then print("Evil CVE-2013-2729") end
return 1
end
return 0
end
function suspicious_string_search(js,verbose)
local ret = 0
local fnd = nil
_,_,fnd = string.find(js,">(SUkqADggAA[^<]-)<")
if fnd ~= nil then
local tiffdata = apr.base64_decode(fnd)
if struct.unpack("<I4",string.sub(tiffdata,5,8)) == 0x2038 then
if verbose == 1 then
print ("likely CVE-2010-0188 PDF")
ret = 1
else
return 1
end
end
end
_,_,fnd = string.find(js,">(TU0AKgAA[^<]-)<")
if fnd ~= nil then
local tiffdata = apr.base64_decode(fnd)
if struct.unpack(">I4",string.sub(tiffdata,5,8)) == 0x2038 then
if verbose == 1 then
print ("likely CVE-2010-0188 PDF")
ret = 1
else
return 1
end
end
end
fnd = string.find(js,"\044\036\036\036\036\058\040\033\091\093\043\034\034\041\091",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found JJEncoded Script")
ret = 1
else
return 1
end
end
--Evertyhing below this line has quotes and + removed
js = string.gsub(js,"[\034\039%+]","")
fnd = string.find(js,"=%[XA%(%(%d%),0-[A-F0-9]-%),XA%(%(%d%),0-[A-F0-9]-%),XA%(%(%d%),0-[A-F0-9]-%)")
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found Sytx/Cool PDF")
ret = 1
else
return 1
end
end
fnd = string.find(js,"ImageField1.ZZA(321,513613",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found BHEK PDF")
ret = 1
else
return 1
end
end
fnd = string.find(js,"charCodeAt",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found charCodeAt in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,".replace",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found .replace in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,"eval%(",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found eval in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,"unescape",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found unescape in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,"This Program Cannot Be Run in DOS Mode",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found This Program Cannot Be Run in DOS")
ret = 1
else
return 1
end
end
fnd = string.find(js,"app.setTimeOut",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found app.setTimeOut in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,"\092u4f4f\092u4f4f",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found \092u4f4f\092u4f4f Spray String in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,"u9090",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found u9090 Spray String in JS")
ret = 1
else
return 1
end
end
fnd = string.find(js,".fromCharCode",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found .fromCharCode")
ret = 1
else
return 1
end
end
fnd = string.find(js,".substr%(",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found .substr%(")
ret = 1
else
return 1
end
end
fnd = string.find(js,"function[\r\n%s]-heapSpray")
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found function heapSpray")
ret = 1
else
return 1
end
end
fnd = string.find(js,"^^^^e^^^^v^^^^a^^^^l^^^^(^^^^v",0,true)
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found Nuclear PDF")
ret = 1
else
return 1
end
end
fnd = string.find(js,"6xFYuX.FAABJgDQI..XJdff\0474Ojq\047\047\047")
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found Fiesta PDF")
ret = 1
else
return 1
end
end
_,_,fnd,m1,m2 = string.find(js,"(\093\059([a-z0-9][a-z0-9][a-z0-9]?)=parseInt%([a-z0-9][a-z0-9][a-z0-9]?,16%)\059([a-z0-9][a-z0-9][a-z0-9]?)=%3[a-z0-9][a-z0-9][a-z0-9]?%(%2%)\125return %3\125)")
if fnd ~= nil then
if verbose == 1 then
print("Suspicous: Found Fiesta PDF M2 " .. fnd)
ret = 1
else
return 1
end
end
--CVE-2013-3346
if string.find(js,"app.removeToolButton",0,true) ~= nil then
function_table = {}
add_button_table = {}
--iterate over the fuctions
for fname,f in string.gmatch(js,"(%w+)[\r\n%s]-=[\r\n%s]-function[\r\n%s]-%([^%)]-%)[\r\n%s]-(%b{})") do
function_table[fname]=f
end
for fname,f in string.gmatch(js,"function[\r\n%s]+(%w+)[\r\n%s]-%([^%)]-%)[\r\n%s]-(%b{})") do
function_table[fname]=f
end
for i, v in pairs(function_table) do
_,_,remove_button_function = string.find(v,"app.removeToolButton[\r\n%s]-%((%b{})")
if remove_button_function ~= nil then
_,_,removecname = string.find(remove_button_function,"cName[\r\n%s]-:[\r\n%s]-([^\r\n%s,%}]+)")
for add_button in string.gmatch(js,"app.addToolButton[\r\n%s]-%([\r\n%s]-(%b{})") do
if string.find(add_button,"cName[\r\n%s]-:[\r\n%s]-"..removecname) ~= nil then
_,_,enablefunc = string.find(add_button,"cEnable[\r\n%s]-:[\r\n%s]-([^\r\n%s%,%}%(]+)")
if function_table[enablefunc] ~= nil then
fnd = string.find(function_table[enablefunc],"cEnable[\r\n%s]-:[\r\n%s]-"..i)
if fnd ~= nil then
if verbose == 1 then
print("Found CVE-2013-3346")
ret = 1
else
return 1
end
end
end
end
end
end
end
local cexec = nil
local button_name = nil
for add_button in string.gmatch(js,"app.addToolButton[\r\n%s]-%([\r\n%s]-(%b{})") do
print(add_button)
_,_,cname = string.find(add_button,"cName[\r\n%s]-:[\r\n%s]-([^\r\n%s%,%}%(]+)")
if cname ~= nil and string.find(add_button,"cExec[\r\n%s]-:.-app.removeToolButton[\r\n%s]-%("..cname.."[\r\n%s]-%)") ~= nil then
if verbose == 1 then
print("Found CVE-2013-3346")
ret = 1
else
return 1
end
end
end
end
----[[ _,_,fnd = string.find(js,"return%([ \r%s]-[\034\039]([a-zA-Z0-9%+]-)[\034\039]")
if fnd ~= nil and string.len(fnd) > 512 then
if verbose == 1 then
print("Suspicous: Found return of static hex string longer than 512 chars")
ret = 1
else
return 1
end
end
--]]--
return ret
end
-- Replace this. It is actually a really dumb way to deal with >> in stream data
function parse_object(obj_data,verbose)
local stream_data,sstart,send = nil
local stream_data_final = nil
local dict_start,dict_end,tag_data = string.find(obj_data,"<<(.*)>>")
if tag_data ~= nil then
if string.find(tag_data,">>[\r\n%s%%]*stream[%s\r\n]*") ~= nil then
_,_,tag_data = string.find(obj_data,"^(.*)>>[\r\n%s%%]*stream[%s\r\n]*",dict_start+2)
dict_end = dict_start + string.len(tag_data) + 3
end
_,stream_start = string.find(obj_data,"^[\r\n%s%%]*stream[%s\r\n]*",dict_end+1)
tag_data=(AsciiHexDecodePound(tag_data))
if stream_start ~= nil then
if string.find(tag_data,'FlateDecode') ~= nil and string.find(tag_data,'ObjStm') ~= nil then
_,_,offset = string.find(tag_data,'First%s*(%d+)')
if offset ~= nil then
--print(offset)
stream_start = stream_start + offset
end
end
local sstart,send,stream_data = string.find(obj_data,"^(.-)\n?endstream",stream_start+1)
--this is a pretty dumb way to deal with this we should parse all Filters and process them in an ordered list but since we only support 2 right now....
if string.find(tag_data,'\047Filter[\r\n%s]-\047FlateDecode') ~= nil or string.find(tag_data,'\047Filter[\r\n%s]-%[[\r\n%s]-\047FlateDecode[\r\n%s]-]') ~= nil then
stream_data_final = FlateDecode(stream_data)
elseif string.find(tag_data,'\047Filter[\r\n%s]-\047ASCIIHexDecode') ~= nil or string.find(tag_data,'\047Filter[\r\n%s]-%[?[\r\n%s]-\047ASCIIHexDecode[\r\n%s]-%]?') ~= nil then
stream_data_final = AsciiHexDecode(stream_data)
elseif string.find(tag_data,'\047Filter[\r\n%s]-%[[\r\n%s]-\047ASCIIHexDecode[\r\n%s]-\047FlateDecode[\r\n%s]-%]') ~= nil then
stream_data = AsciiHexDecode(stream_data)
stream_data_final = FlateDecode(stream_data)
elseif string.find(tag_data,'\047Filter[\r\n%s]-%[[\r\n%s]-\047FlateDecode[\r\n%s]-\047ASCIIHexDecode[\r\n%s]-%]') ~= nil then
stream_data = FlateDecode(stream_data)
stream_data_final = AsciiHexDecode(stream_data)
else
stream_data_final = stream_data
end
end
end
--[[
if verbose == 1 then
if tag_data ~= nil then
print("--obj data--\n" .. tag_data .. "\n--obj data--")
end
if stream_data_final ~= nil then
print("--stream data--\n" .. stream_data_final .. "\n--stream data--")
print(stream_data_final)
end
end
]]--
return {tag_data,stream_data_final}
end
function populate_objects_table(pdf,pdf_objects_tbl,verbose)
for obj_num,obj_data in string.gfind(pdf,"\n?(%d+%s+%d+)%s+obj%s*(.-)%s*\n?endobj") do
pdf_objects_tbl[obj_num]=parse_object(obj_data,verbose)
end
end
function AsciiHexDecode(t)
t = string.gsub(t,"%s","")
local decoded = string.gsub(t,"(%x%x)", function(h) return string.char(tonumber(h,16)) end)
return decoded
end
function FlateDecode(t)
local stream = lz.inflate()
stream_data_final, eof, bytes_in, uncompressed_len = stream(t)
return stream_data_final
end
function AsciiHexDecodePound(t)
local decoded = string.gsub(t,"#(%x%x)",function(h) return string.char(tonumber(h,16)) end)
return decoded
end
function common(t,verbose)
local ret = 0
local tret = 0
pdf_objects_tbl={}
populate_objects_table(t,pdf_objects_tbl,verbose)
for k,v in pairs(pdf_objects_tbl) do
if pdf_objects_tbl[k][1] ~= nil then
if pdf_objects_tbl[k][2] then
tret = cve_2013_2729(tostring(pdf_objects_tbl[k][2]),verbose)
if tret == 1 then
if verbose == 1 then
ret = 1
else
return 1
end
end
tret = suspicious_string_search(tostring(pdf_objects_tbl[k][2]),verbose)
if tret == 1 then
if verbose == 1 then
ret = 1
else
return 1
end
end
end
end
end
return ret
end
function match(args)
local t = tostring(args["http.response_body"])
local o = args["offset"]
ret=common(t,0)
return ret
end
function run()
local f = io.open(arg[1])
local t = f:read("*all")
f:close()
common(t,1)
end