{"cve":"CVE-2026-93174","nvd":{"published":"2026-09-17T17:18:13.167","modified":"2026-10-19T10:17:07.773","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Copy per-CPU map value padding in copy_map_value_long()\n\nIn kernel, per-CPU map elements are stored with\nround_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the\nrounded size for each CPU into a temporary buffer.\n\nHowever, copy_map_value_long() passes 'map->value_size' to\nbpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies\naround those fields with memcpy(), and does not copy the tail padding\nbetween 'map->value_size' and round_up(map->value_size, 8).\n\nThe temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a\nresult, when the per-CPU map's value size is not equal to\nround_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return\nstale heap contents from that padding to user space. The same issue\napplies to bpf_iter for per-CPU maps.\n\nPass round_up(map->value_size, 8) to bpf_obj_memcpy() from\ncopy_map_value_long(), so per-CPU maps both with and without special\nfields copy the entire per-CPU slot. Remove the now redundant round_up()\nfrom bpf_obj_memcpy()'s long_memcpy path.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/003bf840ed3326bd01396ce7d5b431cef0d371e7","https://git.kernel.org/stable/c/5e9f69829835521aa2942d1d14bd0990fbc6991e","https://git.kernel.org/stable/c/7cf9cd98cf6f0df3befc167ca6b54c07014d71de","https://git.kernel.org/stable/c/953e85da53541a8dc3e7ad4e8532f29a34a32eae","https://git.kernel.org/stable/c/ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-93174","score":0.00168,"percentile":0.05979,"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."]}