From: Nicolas Dufresne Date: Wed, 9 Aug 2023 12:49:19 -0400 Subject: h265parser: Fix possible overflow using max_sub_layers_minus1 Origin: https://gitlab.freedesktop.org/gstreamer/gstreamer/-/commit/fddda166222a067d0e511950a0a8cfb9f5a521b7 Bug-Debian: https://bugs.debian.org/1053259 Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2023-40476 This fixes a possible overflow that can be triggered by an invalid value of max_sub_layers_minus1 being set in the bitstream. The bitstream uses 3 bits, but the allowed range is 0 to 6 only. Fixes ZDI-CAN-21768, CVE-2023-40476 Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/2895 Part-of: --- .../gst-plugins-bad/gst-libs/gst/codecparsers/gsth265parser.c | 2 ++ 1 file changed, 2 insertions(+) --- a/gst-libs/gst/codecparsers/gsth265parser.c +++ b/gst-libs/gst/codecparsers/gsth265parser.c @@ -1845,6 +1845,7 @@ gst_h265_parse_vps (GstH265NalUnit * nal READ_UINT8 (&nr, vps->max_layers_minus1, 6); READ_UINT8 (&nr, vps->max_sub_layers_minus1, 3); + CHECK_ALLOWED (vps->max_sub_layers_minus1, 0, 6); READ_UINT8 (&nr, vps->temporal_id_nesting_flag, 1); /* skip reserved_0xffff_16bits */ @@ -2015,6 +2016,7 @@ gst_h265_parse_sps (GstH265Parser * pars READ_UINT8 (&nr, sps->vps_id, 4); READ_UINT8 (&nr, sps->max_sub_layers_minus1, 3); + CHECK_ALLOWED (sps->max_sub_layers_minus1, 0, 6); READ_UINT8 (&nr, sps->temporal_id_nesting_flag, 1); if (!gst_h265_parse_profile_tier_level (&sps->profile_tier_level, &nr,