CVE-2022-47653: buffer overflow in eac3_update_channels function of media_tools/av_parsers.c:9113 · Issue #2349 · gpac/gpac

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Description

buffer overflow in eac3_update_channels function of media_tools/av_parsers.c:9113

static void eac3_update_channels(GF_AC3Config *hdr) { u32 i; for (i=0; i<hdr->nb_streams; i++) { u32 nb_ch = ac3_mod_to_total_chans[hdr->streams[i].acmod]; // overflow if (hdr->streams[i].nb_dep_sub) { hdr->streams[i].chan_loc = eac3_chanmap_to_chan_loc(hdr->streams[i].chan_loc); nb_ch += gf_eac3_get_chan_loc_count(hdr->streams[i].chan_loc); } if (hdr->streams[i].lfon) nb_ch++; hdr->streams[i].channels = nb_ch; hdr->streams[i].surround_channels = ac3_mod_to_surround_chans[hdr->streams[i].acmod]; } }

Version info

latest version

MP4Box - GPAC version 2.1-DEV-rev593-g007bf61a0-master
(c) 2000-2022 Telecom Paris distributed under LGPL v2.1+ - http://gpac.io

Please cite our work in your research:
    GPAC Filters: https://doi.org/10.1145/3339825.3394929
    GPAC: https://doi.org/10.1145/1291233.1291452

GPAC Configuration: --enable-sanitizer
Features: GPAC_CONFIG_LINUX GPAC_64_BITS GPAC_HAS_IPV6 GPAC_HAS_SSL GPAC_HAS_SOCK_UN GPAC_MINIMAL_ODF GPAC_HAS_QJS GPAC_HAS_LINUX_DVB  GPAC_DISABLE_3D

Reproduce

compile and run

./configure --enable-sanitizer
make
./MP4Box import -add poc_bof7.swf

Crash reported by sanitizer

[iso file] Unknown box type dvbs in parent stsd
Track Importing EAC-3 - SampleRate 32000 Num Channels 6
[AC3Dmx] 24 bytes unrecovered before sync word
[AC3Dmx] 13 bytes unrecovered before sync word
media_tools/av_parsers.c:9113:50: runtime error: index 8 out of bounds for type 'GF_AC3StreamInfo [8]'

POC

poc_bof7.zip

Impact

Potentially causing DoS and RCE

Credit

Xdchase