aa_read_header in libavformat/aadec.c in FFmpeg before 3.2.14 and 4.x before 4.1.4 does not check for sscanf failure and consequently allows use of uninitialized variables.
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:HI:HA:H9.8/CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H