Null pointer dereference vulnerability in ic_predict (libfaad/ic_predict.c:96)

[fantasy7082]

Hi, i found a null pointer dereference bug in Freeware Advanced Audio Decoder 2 (FAAD2) 2.8.8. It crashed in function ic_predict .the details are below(ASAN):

./faad faad_res/005-null-point-ic_predict_96 -o out.wav
 *********** Ahead Software MPEG-4 AAC Decoder V2.8.8 ******************

 Build: Dec 13 2018
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 bug tracking: https://sourceforge.net/p/faac/bugs/
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

faad_res/005-null-point-ic_predict_96 file info:
ADTS, 0.021 sec, 219 kbps, 96000 Hz

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Center front   |
 | 01 | Center back    |
  ---------------------

ASAN:SIGSEGVfaad_res/005-null-point-ic_predict_96.
=================================================================
==7073==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x7f440069b99e bp 0x7ffe0d2d4b70 sp 0x7ffe0d2d49f0 T0)
    #0 0x7f440069b99d in ic_predict /root/faad2_asan/libfaad/ic_predict.c:96
    #1 0x7f440069cbc0 in ic_prediction /root/faad2_asan/libfaad/ic_predict.c:252
    #2 0x7f44006d0a14 in reconstruct_channel_pair /root/faad2_asan/libfaad/specrec.c:1189
    #3 0x7f44006d8823 in channel_pair_element /root/faad2_asan/libfaad/syntax.c:759
    #4 0x7f44006d6cbf in decode_cpe /root/faad2_asan/libfaad/syntax.c:402
    #5 0x7f44006d7398 in raw_data_block /root/faad2_asan/libfaad/syntax.c:448
    #6 0x7f44006919c3 in aac_frame_decode /root/faad2_asan/libfaad/decoder.c:990
    #7 0x7f4400691566 in NeAACDecDecode /root/faad2_asan/libfaad/decoder.c:821
    #8 0x40f8ae in decodeAACfile /root/faad2_asan/frontend/main.c:679
    #9 0x411dd4 in faad_main /root/faad2_asan/frontend/main.c:1323
    #10 0x411fe5 in main /root/faad2_asan/frontend/main.c:1366
    #11 0x7f44002c982f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)
    #12 0x401aa8 in _start (/usr/local/faad-asan/bin/faad+0x401aa8)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /root/faad2_asan/libfaad/ic_predict.c:96 ic_predict
==7073==ABORTING

POC FILE:https://github.com/fantasy7082/image_test/blob/master/005-null-point-ic_predict_96

[nluedtke]

This was assigned CVE-2018-20195.

[hlef]

Not reproducible on master anymore, fixed by 466b01d.

This is the same issue as #26, different path, so this can be closed.

[fabiangreffrath]

It's a pleasure.