CVE-2026-31593

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Reject attempts to sync VMSA of an already-launched/encrypted vCPU Reject synchronizing vCPU state to its associated VMSA if the vCPU has already been launched, i.e. if the VMSA has already been encrypted. On a host with SNP enabled, accessing guest-private memory generates an RMP #PF and panics the host. BUG: unable to handle page fault for address: ff1276cbfdf36000 #PF: supervisor write access in kernel mode #PF: error_code(0x80000003) - RMP violation PGD 5a31801067 P4D 5a31802067 PUD 40ccfb5063 PMD 40e5954063 PTE 80000040fdf36163 SEV-SNP: PFN 0x40fdf36, RMP entry: [0x6010fffffffff001 - 0x000000000000001f] Oops: Oops: 0003 [#1] SMP NOPTI CPU: 33 UID: 0 PID: 996180 Comm: qemu-system-x86 Tainted: G OE Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Dell Inc. PowerEdge R7625/0H1TJT, BIOS 1.5.8 07/21/2023 RIP: 0010:sev_es_sync_vmsa+0x54/0x4c0 [kvm_amd] Call Trace: <TASK> snp_launch_update_vmsa+0x19d/0x290 [kvm_amd] snp_launch_finish+0xb6/0x380 [kvm_amd] sev_mem_enc_ioctl+0x14e/0x720 [kvm_amd] kvm_arch_vm_ioctl+0x837/0xcf0 [kvm] kvm_vm_ioctl+0x3fd/0xcc0 [kvm] __x64_sys_ioctl+0xa3/0x100 x64_sys_call+0xfe0/0x2350 do_syscall_64+0x81/0x10f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7ffff673287d </TASK> Note, the KVM flaw has been present since commit ad73109ae7ec ("KVM: SVM: Provide support to launch and run an SEV-ES guest"), but has only been actively dangerous for the host since SNP support was added. With SEV-ES, KVM would "just" clobber guest state, which is totally fine from a host kernel perspective since userspace can clobber guest state any time before sev_launch_update_vmsa().
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

29 Apr 2026, 14:29

Type Values Removed Values Added
CWE NVD-CWE-noinfo
First Time Linux
Linux linux Kernel
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/692fdf05e55fa03960a1278afdc2478c12daea13 - () https://git.kernel.org/stable/c/692fdf05e55fa03960a1278afdc2478c12daea13 - Patch
References () https://git.kernel.org/stable/c/6ef109e01e1d35199e1a97ea68bdfd3cf3fbf9ab - () https://git.kernel.org/stable/c/6ef109e01e1d35199e1a97ea68bdfd3cf3fbf9ab - Patch
References () https://git.kernel.org/stable/c/8f85a4885eee8cb495961ffa371a91828afb9445 - () https://git.kernel.org/stable/c/8f85a4885eee8cb495961ffa371a91828afb9445 - Patch
References () https://git.kernel.org/stable/c/9b9f7962e3e879d12da2bf47e02a24ec51690e3d - () https://git.kernel.org/stable/c/9b9f7962e3e879d12da2bf47e02a24ec51690e3d - Patch
References () https://git.kernel.org/stable/c/c9609847ae65ca36233077c2b6cb2bc0fb37c77a - () https://git.kernel.org/stable/c/c9609847ae65ca36233077c2b6cb2bc0fb37c77a - Patch

27 Apr 2026, 12:16

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/9b9f7962e3e879d12da2bf47e02a24ec51690e3d -

24 Apr 2026, 15:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-04-24 15:16

Updated : 2026-04-29 14:29


NVD link : CVE-2026-31593

Mitre link : CVE-2026-31593

CVE.ORG link : CVE-2026-31593


JSON object : View

Products Affected

linux

  • linux_kernel