{"cve":"CVE-2025-40255","nvd":{"published":"2025-12-04T16:16:19.227","modified":"2026-10-19T19:10:00.130","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: core: prevent NULL deref in generic_hwtstamp_ioctl_lower()\n\nThe ethtool tsconfig Netlink path can trigger a null pointer\ndereference. A call chain such as:\n\n  tsconfig_prepare_data() ->\n  dev_get_hwtstamp_phylib() ->\n  vlan_hwtstamp_get() ->\n  generic_hwtstamp_get_lower() ->\n  generic_hwtstamp_ioctl_lower()\n\nresults in generic_hwtstamp_ioctl_lower() being called with\nkernel_cfg->ifr as NULL.\n\nThe generic_hwtstamp_ioctl_lower() function does not expect\na NULL ifr and dereferences it, leading to a system crash.\n\nFix this by adding a NULL check for kernel_cfg->ifr in\ngeneric_hwtstamp_ioctl_lower(). If ifr is NULL, return -EINVAL.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/8817f816ae41908e9625c0770c4af0dcdcc01238","https://git.kernel.org/stable/c/f796a8dec9beafcc0f6f0d3478ed685a15c5e062"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2025-40255","score":0.00186,"percentile":0.08149,"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."]}