{"cve":"CVE-2025-38257","nvd":{"published":"2025-07-09T11:15:27.993","modified":"2026-10-15T22:18:37.177","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/pkey: Prevent overflow in size calculation for memdup_user()\n\nNumber of apqn target list entries contained in 'nr_apqns' variable is\ndetermined by userspace via an ioctl call so the result of the product in\ncalculation of size passed to memdup_user() may overflow.\n\nIn this case the actual size of the allocated area and the value\ndescribing it won't be in sync leading to various types of unpredictable\nbehaviour later.\n\nUse a proper memdup_array_user() helper which returns an error if an\noverflow is detected. Note that it is different from when nr_apqns is\ninitially zero - that case is considered valid and should be handled in\nsubsequent pkey_handler implementations.\n\nFound by Linux Verification Center (linuxtesting.org).","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/73483ca7e07a5e39bdf612eec9d3d293e8bef649","https://git.kernel.org/stable/c/7360ee47599af91a1d5f4e74d635d9408a54e489","https://git.kernel.org/stable/c/88f3869649edbc4a13f6c2877091f81cd5a50f05","https://git.kernel.org/stable/c/ad1bdd24a02d5a8d119af8e4cd50933780a6d29f","https://git.kernel.org/stable/c/f855b119e62b004a5044ed565f2a2b368c4d3f16"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:04:28.436527499+00:00"},"epss":{"cve":"CVE-2025-38257","score":0.00179,"percentile":0.07435,"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."]}