Linux Kernel up to 6.17-rc2 resctrl_cpu_detect divide by zero

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.17-rc2. It has been declared as critical. This affects the function resctrl_cpu_detect. Such manipulation leads to divide by zero. This vulnerability is traded as CVE-2025-39681. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.17-rc2. It has been rated as critical. Affected by this issue is the function resctrl_cpu_detect. The manipulation with an unknown input leads to a divide by zero vulnerability. Using CWE to declare the problem leads to CWE-369. The product divides a value by zero. Impacted is availability. CVE summarizes:

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. ]

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2025-39681 since 04/16/2025. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 261651 (Linux Distros Unpatched Vulnerability : CVE-2025-39681), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.190, 6.1.149, 6.6.103, 6.12.44, 6.16.4 or 6.17-rc3 eliminates this vulnerability. Applying the patch 873f32201df8876bdb2563e3187e79149427cab4/fb81222c1559f89bfe3aa1010f6d112531d55353/7207923d8453ebfb35667c1736169f2dd796772e/a9e5924daa954c9f585c1ca00358afe71d6781c4/d23264c257a70dbe021b43b3bc2ee16134cd2c69/d8df126349dad855cdfedd6bbf315bad2e901c2f is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (261651) and CERT Bund (WID-SEC-2025-1988). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• NetApp FAS
• NetApp AFF
• NetApp ActiveIQ Unified Manager
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• Microsoft Azure
• Dell Secure Connect Gateway
• IBM QRadar SIEM
• IBM Security Verify Access
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.189
• 6.1.148
• 6.6.102
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.17-rc1
• 6.17-rc2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion