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. ]

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Linux
  • Linux Kernel

No data.

No data.

References
Link Providers
https://git.kernel.org/stable/c/62f12cde10118253348a7540e85606869bd69432 cve-icon cve-icon
https://git.kernel.org/stable/c/7207923d8453ebfb35667c1736169f2dd796772e cve-icon cve-icon
https://git.kernel.org/stable/c/873f32201df8876bdb2563e3187e79149427cab4 cve-icon cve-icon
https://git.kernel.org/stable/c/a9e5924daa954c9f585c1ca00358afe71d6781c4 cve-icon cve-icon
https://git.kernel.org/stable/c/d23264c257a70dbe021b43b3bc2ee16134cd2c69 cve-icon cve-icon
https://git.kernel.org/stable/c/d8df126349dad855cdfedd6bbf315bad2e901c2f cve-icon cve-icon
https://git.kernel.org/stable/c/fb81222c1559f89bfe3aa1010f6d112531d55353 cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2025090545-CVE-2025-39681-ac80@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2025-39681 cve-icon
https://www.cve.org/CVERecord?id=CVE-2025-39681 cve-icon
History

Mon, 08 Sep 2025 06:30:00 +0000

Type Values Removed Values Added
References

Sun, 07 Sep 2025 16:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Vendors & Products Linux
Linux linux Kernel

Sat, 06 Sep 2025 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

Fri, 05 Sep 2025 17:30:00 +0000

Type Values Removed Values Added
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. ]
Title x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper
References
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2025-09-05T17:20:47.564Z

Updated: 2025-09-08T06:21:59.546Z

Reserved: 2025-04-16T07:20:57.113Z

Link: CVE-2025-39681

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-09-05T18:15:44.537

Modified: 2025-09-08T16:25:38.810

Link: CVE-2025-39681

cve-icon Redhat

Severity : Low

Publid Date: 2025-09-05T00:00:00Z

Links: CVE-2025-39681 - Bugzilla