cbcvebase.
CVE-2025-40038
published 2025-10-28

CVE-2025-40038: In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Skip fastpath emulation on VM-Exit if next RIP isn't valid Skip the WRMSR and HLT…

PriorityP425high7.1CVSS 3.1
AVLACLPRNUINSCCNINAH
EPSS
0.17%
6.2th percentile
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Skip fastpath emulation on VM-Exit if next RIP isn't valid Skip the WRMSR and HLT fastpaths in SVM's VM-Exit handler if the next RIP isn't valid, e.g. because KVM is running with nrips=false. SVM must decode and emulate to skip the instruction if the CPU doesn't provide the next RIP, and getting the instruction bytes to decode requires reading guest memory. Reading guest memory through the emulator can fault, i.e. can sleep, which is disallowed since the fastpath handlers run with IRQs disabled. BUG: sleeping function called from invalid context at ./include/linux/uaccess.h:106 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 32611, name: qemu preempt_count: 1, expected: 0 INFO: lockdep is turned off. irq event stamp: 30580 hardirqs last enabled at (30579): [] vcpu_run+0x1787/0x1db0 [kvm] hardirqs last disabled at (30580): [] __schedule+0x1e2/0xed0 softirqs last enabled at (30570): [] fpu_swap_kvm_fpstate+0x44/0x210 softirqs last disabled at (30568): [] fpu_swap_kvm_fpstate+0x44/0x210 CPU: 298 UID: 0 PID: 32611 Comm: qemu Tainted: G U 6.16.0-smp--e6c618b51cfe-sleep #782 NONE Tainted: [U]=USER Hardware name: Google Astoria-Turin/astoria, BIOS 0.20241223.2-0 01/17/2025 Call Trace: dump_stack_lvl+0x7d/0xb0 __might_resched+0x271/0x290 __might_fault+0x28/0x80 kvm_vcpu_read_guest_page+0x8d/0xc0 [kvm] kvm_fetch_guest_virt+0x92/0xc0 [kvm] __do_insn_fetch_bytes+0xf3/0x1e0 [kvm] x86_decode_insn+0xd1/0x1010 [kvm] x86_emulate_instruction+0x105/0x810 [kvm] __svm_skip_emulated_instruction+0xc4/0x140 [kvm_amd] handle_fastpath_invd+0xc4/0x1a0 [kvm] vcpu_run+0x11a1/0x1db0 [kvm] kvm_arch_vcpu_ioctl_run+0x5cc/0x730 [kvm] kvm_vcpu_ioctl+0x578/0x6a0 [kvm] __se_sys_ioctl+0x6d/0xb0 do_syscall_64+0x8a/0x2c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f479d57a94b Note, this is essentially a reapply of commit 5c30e8101e8d ("KVM: SVM: Skip WRMSR fastpath on VM-Exit if next RIP isn't valid"), bu

Affected

17 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.6-1 (forky)linux 6.17.6-1 (forky)
linuxlinux
linuxlinux>= b439eb8ab578557263815ba8581d02c1b730e348 < cd3efb93677c4b0cf76348882fb429165fee33fdcd3efb93677c4b0cf76348882fb429165fee33fd
linuxlinux>= b439eb8ab578557263815ba8581d02c1b730e348 < f994e9c790ce97d3cf01af4d0a1b9add0c955aeef994e9c790ce97d3cf01af4d0a1b9add0c955aee
linuxlinux>= b439eb8ab578557263815ba8581d02c1b730e348 < da2a3c231f7f2a5ac146d972b8c1d7d84aff6d70da2a3c231f7f2a5ac146d972b8c1d7d84aff6d70
linuxlinux>= b439eb8ab578557263815ba8581d02c1b730e348 < 0910dd7c9ad45a2605c45fd2bf3d1bcac087687c0910dd7c9ad45a2605c45fd2bf3d1bcac087687c
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 6.13.0 < 6.17.36.17.3
linuxlinux_kernel>= 6.5.0 < 6.6.1136.6.113
linuxlinux_kernel>= 6.7.0 < 6.12.536.12.53
msrcazl3_kernel_6.6.104.2-4_on_azure_linux_3.0
ubuntulinux-aws
ubuntulinux-oracle
ubuntulinux-xilinx

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
osv3.2LOW
vendor_ubuntu7.8HIGH
vendor_redhat6.1MEDIUM
vendor_msrc5.5MEDIUM
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.