{"id":"CVE-2026-93045","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject arena frees below the arena base\n\nbpf_arena_free_pages() accepts scalar arena addresses","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject arena frees below the arena base\n\nbpf_arena_free_pages() accepts scalar arena addresses. The runtime\nmasks the address to the low 32 bits and reconstructs a…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","vendor":"Linux","product":"Linux","affected":["Linux >= 317460317a02a1af512697e6e964298dedd8a163 < 90453eaf8f14e7be0ab03983f2a93aeb6b990a58","Linux >= 317460317a02a1af512697e6e964298dedd8a163 < a968dffa5ab3c74d2ebb3a6233bf8b843f0bfc20","Linux >= 317460317a02a1af512697e6e964298dedd8a163 < 8a08635656037aee9c12231ed384449c4ffb1a93","Linux >= 317460317a02a1af512697e6e964298dedd8a163 < b5a71cb2db6d84ac0042549dcec266b18429d41e","Linux 6.9"],"published":"2026-09-17","updated":"2026-09-18","sourceUpdated":"2026-09-18T18:18:19.097","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93045","references":[{"url":"https://git.kernel.org/stable/c/8a08635656037aee9c12231ed384449c4ffb1a93","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/90453eaf8f14e7be0ab03983f2a93aeb6b990a58","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a968dffa5ab3c74d2ebb3a6233bf8b843f0bfc20","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b5a71cb2db6d84ac0042549dcec266b18429d41e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"epss":0.00129,"epssPercentile":0.02863,"ingestedAt":"2026-09-17T16:21:47.773Z","slug":"CVE-2026-93045","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject arena frees below the arena base\n\nbpf_arena_free_pages() accepts scalar arena addresses. The runtime\nmasks the address to the low 32 bits and reconstructs a full user\naddress from the arena base before returning the range to the arena\nfree tree.\n\nWhen the scalar value is below the low 32 bits of the arena base,\nfull_uaddr falls below user_vm_start. The existing upper-end clipping\nthen turns this into an out-of-range free-tree offset. A later\nallocation can reuse that offset and return an address below the arena\nmapping.\n\nReject such frees before computing the clipped range.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":207355,"id":"CVE-2026-93045","ts":1789757341203,"field":"cvss","old":null,"new":"7.8"},{"seq":207354,"id":"CVE-2026-93045","ts":1789757341203,"field":"severity","old":"none","new":"high"}]}