{"id":"CVE-2026-98150","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix BPF_F_CPU validation for sparse CPU IDs\n\nBPF_F_CPU stores the target CPU ID in the upper 32 bits of the map\noperation flags","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix BPF_F_CPU validation for sparse CPU IDs\n\nBPF_F_CPU stores the target CPU ID in the upper 32 bits of the map\noperation flags. bpf_map_check_op_flags() currently…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-787"],"vendor":"Linux","product":"Linux","affected":["Linux >= 2b421662c7887a0649fe409155a1f101562d0fa9 < bdc5941f6eeef90b76a07fd8ca38ac1933ba2195","Linux >= 2b421662c7887a0649fe409155a1f101562d0fa9 < ed54bf564ac52699cf4def3d0c2125d493e756f9","Linux 7.0"],"published":"2026-09-25","updated":"2026-09-30","sourceUpdated":"2026-09-30T14:10:59.253","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98150","references":[{"url":"https://git.kernel.org/stable/c/bdc5941f6eeef90b76a07fd8ca38ac1933ba2195","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ed54bf564ac52699cf4def3d0c2125d493e756f9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98150.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98150"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541321"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98150"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98150"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98150.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00101,"epssPercentile":0.00882,"scores":{"nvd":7,"vendor":5.5,"cna":7},"ingestedAt":"2026-09-25T11:06:38.806Z","slug":"CVE-2026-98150","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix BPF_F_CPU validation for sparse CPU IDs\n\nBPF_F_CPU stores the target CPU ID in the upper 32 bits of the map\noperation flags. bpf_map_check_op_flags() currently compares that ID\nwith num_possible_cpus(), which is the number of possible CPUs rather\nthan a bound on CPU IDs.\n\nOn an arm64 QEMU guest with a CPU device-tree hole, the possible CPU\nmask was 0,2-3. A userspace program using raw bpf() syscalls creates\na BPF_MAP_TYPE_PERCPU_ARRAY and performs update and lookup operations\nfor each CPU by setting BPF_F_CPU and the CPU ID in the flags.\n\nWith the old check, CPU 1 is incorrectly accepted while valid CPU 3 is\nrejected with -ERANGE. The CPU 1 update then reaches the per-CPU map\naccess path and triggers:\n\n  Unable to handle kernel paging request at virtual address ...\n  pc : __pi_memcpy_generic+0x5c/0x22c\n  lr : bpf_percpu_array_update+0x2dc/0x2e8\n  Call trace:\n    __pi_memcpy_generic\n    bpf_map_update_value\n    map_update_elem\n    __sys_bpf\n\nCheck the CPU ID against nr_cpu_ids and cpu_possible() instead. This\nrejects CPU IDs outside the valid range and CPUs absent from the\npossible mask, while allowing valid sparse CPU IDs.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-09-28 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98150.json)","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":210888,"id":"CVE-2026-98150","ts":1790349113037,"field":"cvss","old":null,"new":"7"},{"seq":210887,"id":"CVE-2026-98150","ts":1790349113037,"field":"severity","old":"none","new":"high"}]}