{"id":"CVE-2026-98599","summary":"bpf: Reject non-negative offsets in stack_slot_obj_get_spi()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject non-negative offsets in stack_slot_obj_get_spi()\n\nbpf_get_spi() computes (-off - 1) / BPF_REG_SIZE using C division,\nwhich truncates toward zero. For off == 0, this produces spi 0, the\nsame index used by the valid stack slot at fp-8.\n\nstack_slot_obj_get_spi() currently checks alignment and the resulting\nspi bounds, but does not reject the non-negative offset itself. It can\ntherefore validate a PTR_TO_STACK register holding fp+0 against an\niterator stored at fp-8 even though the runtime receives the actual fp+0\npointer. An effectful iterator kfunc can then interpret memory outside\nthe BPF stack as iterator state.\n\nReject non-negative offsets before converting the offset to an spi. All\nvalid stack objects begin at a negative offset from the frame pointer.","modified":"2026-10-20T02:31:09.059058876Z","published":"2026-10-18T15:19:11.941Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98599.json","cna_assigner":"Linux"},"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/79a9172f3ab4ad8392c5e5c8944b9b7710ade620"},{"type":"WEB","url":"https://git.kernel.org/stable/c/89a7241fc7ecc1b5e47c3f071081e314523b8d9d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98599.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98599"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"06accc8779c1d558a5b5a21f2ac82b0c95827ddd"},{"fixed":"89a7241fc7ecc1b5e47c3f071081e314523b8d9d"},{"fixed":"79a9172f3ab4ad8392c5e5c8944b9b7710ade620"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98599.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.4.0"},{"fixed":"7.2.9"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98599.json"}}],"schema_version":"1.9.0"}