{"id":"CVE-2026-98039","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require MEM_PERCPU for percpu kptr stores\n\nmap_kptr_match_type() treats perm_flags as the set of register type flags\nthat a kptr field permits","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require MEM_PERCPU for percpu kptr stores\n\nmap_kptr_match_type() treats perm_flags as the set of register type flags\nthat a kptr field permits. Adding MEM_PERCPU t…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 36d8bdf75a93190e5669b9d1d95994e13e15ba1d < aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f","Linux >= 36d8bdf75a93190e5669b9d1d95994e13e15ba1d < 0bdd6121c8dd5f1764efe701ce26bb8e15acb172","Linux >= 36d8bdf75a93190e5669b9d1d95994e13e15ba1d < ad4ebae5dbc2d47b544aa54f03c12490065be08a","Linux >= 36d8bdf75a93190e5669b9d1d95994e13e15ba1d < 048029ba1c793f8cabc4ad5eea765da01903f8f1","Linux 6.7"],"published":"2026-09-25","updated":"2026-09-25","sourceUpdated":"2026-09-25T11:17:32.663","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98039","references":[{"url":"https://git.kernel.org/stable/c/048029ba1c793f8cabc4ad5eea765da01903f8f1","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/0bdd6121c8dd5f1764efe701ce26bb8e15acb172","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ad4ebae5dbc2d47b544aa54f03c12490065be08a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-25T11:06:38.850Z","slug":"CVE-2026-98039","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require MEM_PERCPU for percpu kptr stores\n\nmap_kptr_match_type() treats perm_flags as the set of register type flags\nthat a kptr field permits. Adding MEM_PERCPU to that set for\nBPF_KPTR_PERCPU does not require the source register to carry it, however.\nThe subset test consequently accepts both a plain bpf_obj_new() allocation\nand a referenced kernel pointer into a __percpu_kptr map field.\n\nLoads from the field are always marked MEM_PERCPU. Consumers then treat the\nstored value as the cookie returned by bpf_percpu_obj_new(): per-CPU pointer\nhelpers relocate it, and map teardown selects the per-CPU free path. A plain\nallocation can therefore provide an arbitrary kernel read/write, while a\nkernel pointer can be relocated into an invalid address or sent through a\nmissing destructor.\n\nRequire the source MEM_PERCPU flag to match the destination field kind.\nThis preserves valid bpf_percpu_obj_new() stores and rejects both the\nprogram-BTF and kernel-BTF variants.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}