{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "c4d0bfb45068d853a478b9067a95969b1886a30f"
            },
            {
              "fixed": "e472ae0d97865e2021ee668a13eab64013aebf23"
            },
            {
              "fixed": "ca086264e98108b44fdf53971033811a48defe2b"
            },
            {
              "fixed": "ea383b3ea56979ce54c8aa88e6ec67164986c401"
            },
            {
              "fixed": "5403a383f52fc0905703b488f7c3db4b2447dc58"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.10.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98063.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix NULL-ptr-deref in btf_var_show()\n\nbtf_var_show() calls btf_type_id_resolve() unconditionally, which\ndereferences btf-\u003eresolved_ids. That is NULL for a base BTF - e.g. the\nvmlinux BTF that bpf_snprintf_btf() renders against - since base BTF is\nnot resolved during parsing. btf_modifier_show() guards this with\n'if (btf-\u003eresolved_ids)', but btf_var_show() does not.\n\nA BPF program that passes the type_id of a BTF_KIND_VAR from the vmlinux\nBTF to bpf_snprintf_btf() thus NULL-derefs:\n\nKASAN: probably user-memory-access in range [0x46638-0x4663f]\nRIP: 0010:btf_var_show (kernel/bpf/btf.c:2929)\nCall Trace:\n \u003cTASK\u003e\n btf_type_show (kernel/bpf/btf.c:8259)\n btf_type_snprintf_show (kernel/bpf/btf.c:8329)\n bpf_snprintf_btf (kernel/trace/bpf_trace.c:1047)\n bpf_prog_test_run_raw_tp (net/bpf/test_run.c:829)\n __sys_bpf (kernel/bpf/syscall.c:4804)\n do_syscall_64 (arch/x86/entry/syscall_64.c:84)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n \u003c/TASK\u003e\n\nResolve the var's type directly with btf_type_skip_modifiers() when\nresolved_ids is NULL, mirroring btf_modifier_show().",
  "id": "CVE-2026-98063",
  "modified": "2026-09-27T03:30:14.827923284Z",
  "published": "2026-09-25T10:24:07.203Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5403a383f52fc0905703b488f7c3db4b2447dc58"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ca086264e98108b44fdf53971033811a48defe2b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e472ae0d97865e2021ee668a13eab64013aebf23"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ea383b3ea56979ce54c8aa88e6ec67164986c401"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98063.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98063"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "bpf: Fix NULL-ptr-deref in btf_var_show()"
}