{"id":"CVE-2026-43333","title":"bpf: reject direct access to nullable PTR_TO_BUF pointers","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: reject direct access to nullable PTR_TO_BUF pointers\n\ncheck_mem_access() matches PTR_TO_BUF via base_type() which strips\nPTR_MAYBE_NULL, allowing direct dereferenc…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= b453361384c2db1c703dacb806d5fd36aec4ceca < 10bc4a4dcded509c5d5c67d497900c3922c604cd","Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 21a10c06ffae24cb01fd174a7ab7736001d2ea56","Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 8755066f7bd0f4ac46a29d1708c7b20894539252","Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 70abd9d118da2f56beb4ec22e3a29becae373535","Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 63276547debc4d8a73eefb2c5273b2a905c961b0","Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 4f6c99dc0420f1a3d671c1b8ab8a7ac84d9cba09","Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < b0db1accbc7395657c2b79db59fa9fae0d6656f3","Linux e982070f8970bb62e69ed7c9cafff886ed200349","Linux >= 5.15.37 < 5.15.203","Linux >= 5.16.11 < 5.17","Linux 5.17"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T15:35:58.323644Z"},"published":"2026-05-08","updated":"2026-11-06","sourceUpdated":"2026-11-06T15:42:49.460Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-43333","references":[{"url":"https://git.kernel.org/stable/c/10bc4a4dcded509c5d5c67d497900c3922c604cd"},{"url":"https://git.kernel.org/stable/c/21a10c06ffae24cb01fd174a7ab7736001d2ea56"},{"url":"https://git.kernel.org/stable/c/8755066f7bd0f4ac46a29d1708c7b20894539252"},{"url":"https://git.kernel.org/stable/c/70abd9d118da2f56beb4ec22e3a29becae373535"},{"url":"https://git.kernel.org/stable/c/63276547debc4d8a73eefb2c5273b2a905c961b0"},{"url":"https://git.kernel.org/stable/c/4f6c99dc0420f1a3d671c1b8ab8a7ac84d9cba09"},{"url":"https://git.kernel.org/stable/c/b0db1accbc7395657c2b79db59fa9fae0d6656f3"}],"tags":["cve.org"],"epss":0.00123,"epssPercentile":0.02039,"ingestedAt":"2026-11-06T15:54:03.935Z","slug":"CVE-2026-43333","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: reject direct access to nullable PTR_TO_BUF pointers\n\ncheck_mem_access() matches PTR_TO_BUF via base_type() which strips\nPTR_MAYBE_NULL, allowing direct dereference without a null check.\n\nMap iterator ctx->key and ctx->value are PTR_TO_BUF | PTR_MAYBE_NULL.\nOn stop callbacks these are NULL, causing a kernel NULL dereference.\n\nAdd a type_may_be_null() guard to the PTR_TO_BUF branch, matching the\nexisting PTR_TO_BTF_ID pattern.\n\n## Affected\n\n- `Linux >= b453361384c2db1c703dacb806d5fd36aec4ceca < 10bc4a4dcded509c5d5c67d497900c3922c604cd`\n- `Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 21a10c06ffae24cb01fd174a7ab7736001d2ea56`\n- `Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 8755066f7bd0f4ac46a29d1708c7b20894539252`\n- `Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 70abd9d118da2f56beb4ec22e3a29becae373535`\n- `Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 63276547debc4d8a73eefb2c5273b2a905c961b0`\n- `Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < 4f6c99dc0420f1a3d671c1b8ab8a7ac84d9cba09`\n- `Linux >= 20b2aff4bc15bda809f994761d5719827d66c0b4 < b0db1accbc7395657c2b79db59fa9fae0d6656f3`\n- `Linux e982070f8970bb62e69ed7c9cafff886ed200349`\n- `Linux >= 5.15.37 < 5.15.203`\n- `Linux >= 5.16.11 < 5.17`\n- `Linux 5.17`\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":[]}