{"api_version":"1","generated_at":"2026-09-25T22:18:34+00:00","cve":"CVE-2026-98043","urls":{"html":"https://cve.report/CVE-2026-98043","api":"https://cve.report/api/cve/CVE-2026-98043.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98043","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98043"},"summary":{"title":"bpf: Don't infer non-NULL from a pointer with an unbounded offset","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Don't infer non-NULL from a pointer with an unbounded offset\n\nreg_not_null() decides that a register holds a non-NULL value by\nlooking at its type alone. For pointer types that allow arithmetic the\ntype only guarantees a non-NULL base, in case of an unbound offset\nthe runtime offset value might still add up to NULL.\nConsider the followng program:\n\n  r6 = bpf_map_lookup_elem(map, &0);  /* present */\n  if (r6 == 0) return 0;\n  r7 = bpf_map_lookup_elem(map, &1);  /* absent, NULL at runtime */\n  r8 = r7;\n  r8 -= r6;     /* pointer - pointer: unknown scalar, -r6 */\n  r8 <<= 1;\n  r8 >>= 1;     /* any non-negative offset is accepted by */\n                /* check_reg_sane_offset_ptr() */\n  r6 += r8;     /* verifier: map value;    runtime: zero  */\n  if (r7 != r6) return 0;\n  *(u8 *)(r7 + 0);  /* r7 is inferred non-NULL, both are zero */\n\nAt runtime both registers are zero, the comparison is true and the\nload faults with NULL pointer dereference.\n\nRequire the offset to be within +-BPF_MAX_VAR_OFF in reg_not_null().","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:33","updated_at":"2026-09-25 11:17:33"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/67b529f521a6676cdfc78b91b0217d7eaa84216b","name":"https://git.kernel.org/stable/c/67b529f521a6676cdfc78b91b0217d7eaa84216b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/cb6642048739bf4ee5aa09fe465511f1e87caa63","name":"https://git.kernel.org/stable/c/cb6642048739bf4ee5aa09fe465511f1e87caa63","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98043","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98043","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected cac616db39c207dc63465a4e05c6ce0e60b2cce4 cb6642048739bf4ee5aa09fe465511f1e87caa63 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected cac616db39c207dc63465a4e05c6ce0e60b2cce4 67b529f521a6676cdfc78b91b0217d7eaa84216b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.8","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.8 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/bpf/verifier.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"cb6642048739bf4ee5aa09fe465511f1e87caa63","status":"affected","version":"cac616db39c207dc63465a4e05c6ce0e60b2cce4","versionType":"git"},{"lessThan":"67b529f521a6676cdfc78b91b0217d7eaa84216b","status":"affected","version":"cac616db39c207dc63465a4e05c6ce0e60b2cce4","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/bpf/verifier.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.8"},{"lessThan":"5.8","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc2","versionStartIncluding":"5.8","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Don't infer non-NULL from a pointer with an unbounded offset\n\nreg_not_null() decides that a register holds a non-NULL value by\nlooking at its type alone. For pointer types that allow arithmetic the\ntype only guarantees a non-NULL base, in case of an unbound offset\nthe runtime offset value might still add up to NULL.\nConsider the followng program:\n\n  r6 = bpf_map_lookup_elem(map, &0);  /* present */\n  if (r6 == 0) return 0;\n  r7 = bpf_map_lookup_elem(map, &1);  /* absent, NULL at runtime */\n  r8 = r7;\n  r8 -= r6;     /* pointer - pointer: unknown scalar, -r6 */\n  r8 <<= 1;\n  r8 >>= 1;     /* any non-negative offset is accepted by */\n                /* check_reg_sane_offset_ptr() */\n  r6 += r8;     /* verifier: map value;    runtime: zero  */\n  if (r7 != r6) return 0;\n  *(u8 *)(r7 + 0);  /* r7 is inferred non-NULL, both are zero */\n\nAt runtime both registers are zero, the comparison is true and the\nload faults with NULL pointer dereference.\n\nRequire the offset to be within +-BPF_MAX_VAR_OFF in reg_not_null()."}],"providerMetadata":{"dateUpdated":"2026-09-25T10:23:54.865Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/cb6642048739bf4ee5aa09fe465511f1e87caa63"},{"url":"https://git.kernel.org/stable/c/67b529f521a6676cdfc78b91b0217d7eaa84216b"}],"title":"bpf: Don't infer non-NULL from a pointer with an unbounded offset","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98043","datePublished":"2026-09-25T10:23:54.865Z","dateReserved":"2026-09-25T10:19:56.071Z","dateUpdated":"2026-09-25T10:23:54.865Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:33","lastModifiedDate":"2026-09-25 11:17:33","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98043","Ordinal":"1","Title":"bpf: Don't infer non-NULL from a pointer with an unbounded offse","CVE":"CVE-2026-98043","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98043","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Don't infer non-NULL from a pointer with an unbounded offset\n\nreg_not_null() decides that a register holds a non-NULL value by\nlooking at its type alone. For pointer types that allow arithmetic the\ntype only guarantees a non-NULL base, in case of an unbound offset\nthe runtime offset value might still add up to NULL.\nConsider the followng program:\n\n  r6 = bpf_map_lookup_elem(map, &0);  /* present */\n  if (r6 == 0) return 0;\n  r7 = bpf_map_lookup_elem(map, &1);  /* absent, NULL at runtime */\n  r8 = r7;\n  r8 -= r6;     /* pointer - pointer: unknown scalar, -r6 */\n  r8 <<= 1;\n  r8 >>= 1;     /* any non-negative offset is accepted by */\n                /* check_reg_sane_offset_ptr() */\n  r6 += r8;     /* verifier: map value;    runtime: zero  */\n  if (r7 != r6) return 0;\n  *(u8 *)(r7 + 0);  /* r7 is inferred non-NULL, both are zero */\n\nAt runtime both registers are zero, the comparison is true and the\nload faults with NULL pointer dereference.\n\nRequire the offset to be within +-BPF_MAX_VAR_OFF in reg_not_null().","Type":"Description","Title":"bpf: Don't infer non-NULL from a pointer with an unbounded offse"}]}}}