When an authenticated user is denied access to a gRPC method, their authenticated identity remains bound to the gRPC worker thread and can be inherited by a subsequent unauthenticated request on the same thread. This may allow the subsequent user to gain escalated permissions.
Affected versions: Spring gRPC: 1.0.0 - 1.0.2 (fixed in 1.0.3). Older, unsupported versions are also affected.
Exploitability
AV:NAC:HPR:LUI:NScope
S:UImpact
C:LI:LA:N4.2/CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:NOther