In JetBrains Kotlin before 1.4.21, a vulnerable Java API was used for temporary file and folder creation. An attacker was able to read data from such files and list directories due to insecure permissions.
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:LI:NA:N5.3/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N