{"cve":"CVE-2025-39681","nvd":{"published":"2025-09-05T18:15:44.537","modified":"2026-10-19T21:10:00.160","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper\n\nSince\n\n  923f3a2b48bd (\"x86/resctrl: Query LLC monitoring properties once during boot\")\n\nresctrl_cpu_detect() has been moved from common CPU initialization code to\nthe vendor-specific BSP init helper, while Hygon didn't put that call in their\ncode.\n\nThis triggers a division by zero fault during early booting stage on our\nmachines with X86_FEATURE_CQM* supported, where get_rdt_mon_resources() tries\nto calculate mon_l3_config with uninitialized boot_cpu_data.x86_cache_occ_scale.\n\nAdd the missing resctrl_cpu_detect() in the Hygon BSP init helper.\n\n  [ bp: Massage commit message. ]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/62f12cde10118253348a7540e85606869bd69432","https://git.kernel.org/stable/c/7207923d8453ebfb35667c1736169f2dd796772e","https://git.kernel.org/stable/c/873f32201df8876bdb2563e3187e79149427cab4","https://git.kernel.org/stable/c/a9e5924daa954c9f585c1ca00358afe71d6781c4","https://git.kernel.org/stable/c/d23264c257a70dbe021b43b3bc2ee16134cd2c69"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2025-39681","score":0.00176,"percentile":0.07038,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}