{
  "cveId": "CVE-2026-98043",
  "url": "https://patchblox.com/security/cve/CVE-2026-98043",
  "summary": "CVE-2026-98043 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-98043, released October 2, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "bpf: Don\u0027t infer non-NULL from a pointer with an unbounded offset",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  bpf: Don\u0027t infer non-NULL from a pointer with an unbounded offset  reg_not_null() decides that a register holds a non-NULL value by looking at its type alone. For pointer types that allow arithmetic the type only guarantees a non-NULL base, in case of an unbound offset the runtime offset value might still add up to NULL. Consider the followng program:    r6 = bpf_map_lookup_elem(map, \u00260);  /* present */   if (r6 == 0) return 0;   r7 = bpf_map_lookup_elem(map, \u00261);  /* absent, NULL at runtime */   r8 = r7;   r8 -= r6;     /* pointer - pointer: unknown scalar, -r6 */   r8 \u003C\u003C= 1;   r8 \u003E\u003E= 1;     /* any non-negative offset is accepted by */                 /* check_reg_sane_offset_ptr() */   r6 \u002B= r8;     /* verifier: map value;    runtime: zero  */   if (r7 != r6) return 0;   *(u8 *)(r7 \u002B 0);  /* r7 is inferred non-NULL, both are zero */  At runtime both registers are zero, the comparison is true and the load faults with NULL pointer dereference.  Require the offset to be within \u002B-BPF_MAX_VAR_OFF in reg_not_null().",
  "published": "2026-09-25T11:17:33Z",
  "severity": "Moderate",
  "cvss": 5.5,
  "epss": 0.002,
  "epssPercentile": 0.09883,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98043",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.115-2",
      "fix": "DEBIAN-CVE-2026-98043",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-98043",
      "released": "2026-10-02T21:04:56Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.7-1",
      "fix": "DEBIAN-CVE-2026-98043",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-98043",
      "released": "2026-10-02T21:04:56Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}