It was found that the raw midi kernel driver does not protect against concurrent access which leads to a double realloc (double free) in snd_rawmidi_input_params() and snd_rawmidi_output_status() which are part of snd_rawmidi_ioctl() handler in rawmidi.c file. A malicious local attacker could possibly use this for privilege escalation.
3.13.0-164.2144.4.0-1031.344.15.0-1036.38~14.04.24.4.0-137.163~14.04.14.4.0-137.1634.4.0-1069.794.15.0-1036.38~16.04.14.15.0-1026.27~16.04.14.15.0-43.46~16.04.14.4.0-1035.41Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:HI:HA:HCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H