Linux Distros Unpatched Vulnerability : CVE-2025-71104

high Nessus Plugin ID 284800

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- KVM: x86: Fix VM hard lockup after prolonged inactivity with periodic HV timer When advancing the target expiration for the guest's APIC timer in periodic mode, set the expiration to now if the target expiration is in the past (similar to what is done in update_target_expiration()). Blindly adding the period to the previous target expiration can result in KVM generating a practically unbounded number of hrtimer IRQs due to programming an expired timer over and over. In extreme scenarios, e.g. if userspace pauses/suspends a VM for an extended duration, this can even cause hard lockups in the host. Currently, the bug only affects Intel CPUs when using the hypervisor timer (HV timer), a.k.a. the VMX preemption timer. Unlike the software timer, a.k.a. hrtimer, which KVM keeps running even on exits to userspace, the HV timer only runs while the guest is active. As a result, if the vCPU does not run for an extended duration, there will be a huge gap between the target expiration and the current time the vCPU resumes running. Because the target expiration is incremented by only one period on each timer expiration, this leads to a series of timer expirations occurring rapidly after the vCPU/VM resumes. More critically, when the vCPU first triggers a periodic HV timer expiration after resuming, advancing the expiration by only one period will result in a target expiration in the past. As a result, the delta may be calculated as a negative value. When the delta is converted into an absolute value (tscdeadline is an unsigned u64), the resulting value can overflow what the HV timer is capable of programming. I.e. the large value will exceed the VMX Preemption Timer's maximum bit width of cpu_preemption_timer_multi + 32, and thus cause KVM to switch from the HV timer to the software timer (hrtimers). After switching to the software timer, periodic timer expiration callbacks may be executed consecutively within a single clock interrupt handler, because hrtimers honors KVM's request for an expiration in the past and immediately re-invokes KVM's callback after reprogramming. And because the interrupt handler runs with IRQs disabled, restarting KVM's hrtimer over and over until the target expiration is advanced to now can result in a hard lockup. E.g. the following hard lockup was triggered in the host when running a Windows VM (only relevant because it used the APIC timer in periodic mode) after resuming the VM from a long suspend (in the host). NMI watchdog:
Watchdog detected hard LOCKUP on cpu 45 ... RIP: 0010:advance_periodic_target_expiration+0x4d/0x80 [kvm] ... RSP: 0018:ff4f88f5d98d8ef0 EFLAGS: 00000046 RAX: fff0103f91be678e RBX: fff0103f91be678e RCX:
00843a7d9e127bcc RDX: 0000000000000002 RSI: 0052ca4003697505 RDI: ff440d5bfbdbd500 RBP: ff440d5956f99200 R08: ff2ff2a42deb6a84 R09: 000000000002a6c0 R10: 0122d794016332b3 R11: 0000000000000000 R12:
ff440db1af39cfc0 R13: ff440db1af39cfc0 R14: ffffffffc0d4a560 R15: ff440db1af39d0f8 FS:
00007f04a6ffd700(0000) GS:ff440db1af380000(0000) knlGS:000000e38a3b8000 CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033 CR2: 000000d5651feff8 CR3: 000000684e038002 CR4: 0000000000773ee0 PKRU: 55555554 Call Trace: <IRQ> apic_timer_fn+0x31/0x50 [kvm] __hrtimer_run_queues+0x100/0x280 hrtimer_interrupt+0x100/0x210 ? ttwu_do_wakeup+0x19/0x160 smp_apic_timer_interrupt+0x6a/0x130 apic_timer_interrupt+0xf/0x20 </IRQ> Moreover, if the suspend duration of the virtual machine is not long enough to trigger a hard lockup in this scenario, since commit 98c25ead5eda (KVM: VMX: Move preemption timer <=> hrtimer dance to common x86), KVM will continue using the software timer until the guest reprograms the APIC timer in some way.
Since the periodic timer does not require frequent APIC timer register programming, the guest may continue to use the software timer in ---truncated--- (CVE-2025-71104)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2025-71104

https://security-tracker.debian.org/tracker/CVE-2025-71104

Plugin Details

Severity: High

ID: 284800

File Name: unpatched_CVE_2025_71104.nasl

Version: 1.1

Type: local

Agent: unix

Family: Misc.

Published: 1/15/2026

Updated: 1/15/2026

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.1

CVSS v2

Risk Factor: Medium

Base Score: 5.6

Temporal Score: 4.8

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:C

CVSS Score Source: CVE-2025-71104

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.1

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-rt-core, p-cpe:/a:centos:centos:kernel-rt-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-devel, p-cpe:/a:centos:centos:kernel-rt-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-core, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-doc, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-devel, p-cpe:/a:centos:centos:kernel-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-extra, p-cpe:/a:centos:centos:kernel-kdump-devel, p-cpe:/a:centos:centos:kernel-devel, p-cpe:/a:centos:centos:kernel-rt-64k-modules, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-kvm, p-cpe:/a:centos:centos:kernel-64k-debug, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules, p-cpe:/a:centos:centos:kernel-rt-64k-modules-internal, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:centos:centos:libperf, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-extra, p-cpe:/a:centos:centos:kernel-rt-core, p-cpe:/a:centos:centos:kernel-rt-doc, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug, p-cpe:/a:redhat:enterprise_linux:kernel, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-extra, p-cpe:/a:centos:centos:kernel-kdump, cpe:/o:redhat:enterprise_linux:10, p-cpe:/a:centos:centos:kernel-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-64k-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-extra, p-cpe:/a:centos:centos:kernel-rt-64k-debug-kvm, p-cpe:/a:redhat:enterprise_linux:libperf-devel, p-cpe:/a:centos:centos:kernel-64k-modules-extra, p-cpe:/a:centos:centos:python-perf, p-cpe:/a:redhat:enterprise_linux:kernel-modules, p-cpe:/a:centos:centos:kernel-64k-modules-core, p-cpe:/a:centos:centos:kernel-64k-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-extra, p-cpe:/a:centos:centos:kernel-64k-modules, p-cpe:/a:centos:centos:kernel-rt-devel, p-cpe:/a:centos:centos:kernel-debug-uki-virt-addons, p-cpe:/a:centos:centos:kernel-rt-modules-extra, p-cpe:/a:centos:centos:python3-perf, p-cpe:/a:redhat:enterprise_linux:kernel-rt-selftests-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-modules-partner, p-cpe:/a:centos:centos:kernel-bootwrapper, p-cpe:/a:centos:centos:kernel-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel-matched, cpe:/o:redhat:enterprise_linux:7, p-cpe:/a:centos:centos:kernel-zfcpdump, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace-devel, p-cpe:/a:redhat:enterprise_linux:kernel-bootwrapper, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:python-perf, p-cpe:/a:redhat:enterprise_linux:kernel-64k-core, p-cpe:/a:redhat:enterprise_linux:kernel-abi-whitelists, p-cpe:/a:centos:centos:kernel-64k-debug-modules-internal, p-cpe:/a:centos:centos:kernel-64k-debug-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-internal, p-cpe:/a:centos:centos:kernel-rt-64k-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs-devel, p-cpe:/a:centos:centos:kernel-rt-selftests-internal, p-cpe:/a:centos:centos:kernel-zfcpdump-devel-matched, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-partner, p-cpe:/a:centos:centos:kernel-rt-trace-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-core, p-cpe:/a:redhat:enterprise_linux:kernel-cross-headers, p-cpe:/a:redhat:enterprise_linux:kernel-rt-doc, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs, p-cpe:/a:centos:centos:kernel-debug-devel-matched, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:perf, p-cpe:/a:centos:centos:kernel-64k-devel, p-cpe:/a:redhat:enterprise_linux:kernel-abi-stablelists, p-cpe:/a:centos:centos:kernel-headers, p-cpe:/a:centos:centos:kernel-rt-modules, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-partner, cpe:/o:debian:debian_linux:12.0, p-cpe:/a:redhat:enterprise_linux:kernel-debug-uki-virt, p-cpe:/a:centos:centos:kernel-zfcpdump-modules, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump, p-cpe:/a:centos:centos:kernel-64k-debug-devel, p-cpe:/a:centos:centos:perf, p-cpe:/a:centos:centos:kernel-rt-debug-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-core, p-cpe:/a:centos:centos:kernel-modules, cpe:/o:centos:centos:8, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-extra, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-partner, p-cpe:/a:centos:centos:bpftool, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k, p-cpe:/a:centos:centos:kernel-rt-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules, p-cpe:/a:centos:centos:kernel-64k-devel-matched, p-cpe:/a:centos:centos:kernel-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-modules-internal, p-cpe:/a:centos:centos:kernel-rt-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace-kvm, p-cpe:/a:centos:centos:kernel-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules, p-cpe:/a:redhat:enterprise_linux:kernel-modules-core, p-cpe:/a:centos:centos:kernel-core, p-cpe:/a:centos:centos:kernel-rt-64k-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-kdump-devel, p-cpe:/a:centos:centos:kernel-debug-modules-partner, p-cpe:/a:centos:centos:kernel-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-debug, p-cpe:/a:centos:centos:kernel-rt-debug-core, p-cpe:/a:centos:centos:kernel-devel-matched, p-cpe:/a:centos:centos:kernel-rt-64k-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel, p-cpe:/a:centos:centos:kernel-rt-debug-modules, p-cpe:/a:centos:centos:kernel-rt-64k, p-cpe:/a:centos:centos:kernel, p-cpe:/a:centos:centos:kernel-debug-modules-core, p-cpe:/a:centos:centos:kernel-rt-trace-devel, p-cpe:/a:centos:centos:kernel-rt-64k-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug, p-cpe:/a:centos:centos:kernel-uki-virt-addons, p-cpe:/a:centos:centos:kernel-uki-virt, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-kvm, p-cpe:/a:centos:centos:kernel-64k-debug-devel-matched, p-cpe:/a:centos:centos:kernel-debug-core, p-cpe:/a:centos:centos:kernel-tools-libs-devel, p-cpe:/a:centos:centos:kernel-64k-core, p-cpe:/a:centos:centos:kernel-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:bpftool, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-kvm, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-core, p-cpe:/a:centos:centos:kernel-rt-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-internal, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-devel, p-cpe:/a:centos:centos:kernel-modules-extra-matched, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-devel-matched, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel, p-cpe:/a:centos:centos:kernel-modules-extra, p-cpe:/a:centos:centos:kernel-cross-headers, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-uki-virt-addons, p-cpe:/a:centos:centos:kernel-rt-kvm, p-cpe:/a:centos:centos:kernel-rt-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-partner, p-cpe:/a:debian:debian_linux:linux, p-cpe:/a:centos:centos:kernel-rt, p-cpe:/a:centos:centos:kernel-rt-modules-internal, p-cpe:/a:centos:centos:kernel-tools, p-cpe:/a:centos:centos:kernel-rt-debug-modules-extra, p-cpe:/a:centos:centos:kernel-debug-uki-virt, p-cpe:/a:redhat:enterprise_linux:kernel-kdump, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-extra, cpe:/o:debian:debian_linux:14.0, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-core, p-cpe:/a:centos:centos:kernel-rt-trace, p-cpe:/a:centos:centos:kernel-rt-modules-partner, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules, p-cpe:/a:centos:centos:kernel-rt-debug, p-cpe:/a:redhat:enterprise_linux:kernel-64k-devel-matched, p-cpe:/a:centos:centos:kernel-abi-stablelists, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules, p-cpe:/a:redhat:enterprise_linux:kernel-debug-core, p-cpe:/a:centos:centos:kernel-rt-64k-modules-partner, p-cpe:/a:centos:centos:kernel-rt-64k-debug-core, p-cpe:/a:centos:centos:kernel-doc, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-internal, p-cpe:/a:centos:centos:kernel-rt-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-tools, p-cpe:/a:centos:centos:kernel-rt-64k-modules-core, p-cpe:/a:centos:centos:kernel-zfcpdump-core, p-cpe:/a:centos:centos:kernel-64k-debug-modules-extra, p-cpe:/a:centos:centos:kernel-zfcpdump-devel, p-cpe:/a:centos:centos:kernel-tools-libs, p-cpe:/a:redhat:enterprise_linux:kernel-debug-uki-virt-addons, p-cpe:/a:centos:centos:kernel-abi-whitelists, p-cpe:/a:redhat:enterprise_linux:kernel-64k, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-core, p-cpe:/a:redhat:enterprise_linux:rv, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-uki-virt, cpe:/o:redhat:enterprise_linux:8, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-core, p-cpe:/a:centos:centos:libperf-devel, p-cpe:/a:centos:centos:kernel-64k, p-cpe:/a:redhat:enterprise_linux:kernel-headers, p-cpe:/a:redhat:enterprise_linux:libperf, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-core, p-cpe:/a:centos:centos:kernel-64k-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules, cpe:/o:centos:centos:7, p-cpe:/a:redhat:enterprise_linux:python3-perf, p-cpe:/a:redhat:enterprise_linux:kernel-selftests-internal, p-cpe:/a:centos:centos:kernel-ipaclones-internal, p-cpe:/a:centos:centos:kernel-debug, p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel-matched, p-cpe:/a:centos:centos:rtla, p-cpe:/a:redhat:enterprise_linux:rtla, p-cpe:/a:redhat:enterprise_linux:kernel-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-internal, p-cpe:/a:centos:centos:kernel-rt-64k-modules-extra, p-cpe:/a:centos:centos:kernel-rt-64k-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-core, p-cpe:/a:centos:centos:kernel-64k-debug-modules, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-extra, p-cpe:/a:centos:centos:kernel-selftests-internal, p-cpe:/a:centos:centos:kernel-modules-internal, p-cpe:/a:centos:centos:kernel-debug-modules, p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-ipaclones-internal, p-cpe:/a:centos:centos:kernel-rt-64k-debug, p-cpe:/a:centos:centos:kernel-rt-64k-debug-devel, p-cpe:/a:centos:centos:rv, p-cpe:/a:redhat:enterprise_linux:kernel-rt, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules, p-cpe:/a:redhat:enterprise_linux:kernel-modules-extra-matched

Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 1/14/2026

Reference Information

CVE: CVE-2025-71104