In the mxf_read_primer_pack function in libavformat/mxfdec.c in FFmpeg 3.3.3 -> 2.4, an integer signedness error might occur when a crafted file, which claims a large "item_num" field such as 0xffffffff, is provided. As a result, the variable "item_num" turns negative, bypassing the check for a large value.
http://www.debian.org/security/2017/dsa-3996
http://www.securityfocus.com/bid/100692
https://github.com/FFmpeg/FFmpeg/commit/9d00fb9d70ee8c0cc7002b89318c5be00f1bbdad
https://github.com/FFmpeg/FFmpeg/commit/a4e85b2e1c8d5b4bf0091157bbdeb0e457fb7b8f
https://lists.debian.org/debian-lts-announce/2019/02/msg00005.html
Source: MITRE
Published: 2017-09-07
Updated: 2021-01-04
Type: CWE-20
Base Score: 6.8
Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 8.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 2.8
Severity: HIGH