In the Linux kernel before 6.6.7, an untrusted VMM can trigger int80 syscall handling at any given point. This is related to arch/x86/coco/tdx/tdx.c and arch/x86/mm/mem_encrypt_amd.c.
Exploitability
AV:LAC:LPR:LUI:NScope
S:CImpact
C:HI:HA:H8.8/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H