IM
IronMonkey Threat Research

CVE-2025-39681 MEDIUM

Published: 2025-09-05 | Last Modified: 2026-07-14 | Status: Modified

Description

In the Linux kernel, the following vulnerability has been resolved: x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper Since 923f3a2b48bd ("x86/resctrl: Query LLC monitoring properties once during boot") resctrl_cpu_detect() has been moved from common CPU initialization code to the vendor-specific BSP init helper, while Hygon didn't put that call in their code. This triggers a division by zero fault during early booting stage on our machines with X86_FEATURE_CQM* supported, where get_rdt_mon_resources() tries to calculate mon_l3_config with uninitialized boot_cpu_data.x86_cache_occ_scale. Add the missing resctrl_cpu_detect() in the Hygon BSP init helper. [ bp: Massage commit message. ]

CVSS Metrics

Base Score: 5.5 (MEDIUM)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack VectorLOCAL
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactNONE
Integrity ImpactNONE
Availability ImpactHIGH

Source: [email protected]

Type: Primary

Exploitability Score: 1.8

Impact Score: 3.6

Weaknesses

Source Type Description
[email protected] Primary
en NVD-CWE-noinfo

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7d24246e6a80> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d24246e4dc0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23af076ac0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d246032adc0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d24246e7280> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d24246e6cc0> Operating System
linux linux_kernel 6.17 <built-in method update of dict object at 0x7d23af076800> Operating System
linux linux_kernel 6.17 <built-in method update of dict object at 0x7d23af074e80> Operating System
debian debian_linux 11.0 <built-in method update of dict object at 0x7d23a597bfc0> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References

Notification
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