{"id":"CVE-2026-98039","summary":"bpf: Require MEM_PERCPU for percpu kptr stores","details":"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 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.","modified":"2026-09-26T03:48:37.127901700Z","published":"2026-09-25T10:23:52.360Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98039.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/048029ba1c793f8cabc4ad5eea765da01903f8f1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0bdd6121c8dd5f1764efe701ce26bb8e15acb172"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ad4ebae5dbc2d47b544aa54f03c12490065be08a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98039.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98039"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"36d8bdf75a93190e5669b9d1d95994e13e15ba1d"},{"fixed":"aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f"},{"fixed":"0bdd6121c8dd5f1764efe701ce26bb8e15acb172"},{"fixed":"ad4ebae5dbc2d47b544aa54f03c12490065be08a"},{"fixed":"048029ba1c793f8cabc4ad5eea765da01903f8f1"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98039.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.111"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.53"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98039.json"}}],"schema_version":"1.9.0"}