CVE-2026-98039

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Require MEM_PERCPU for percpu kptr stores map_kptr_match_type() treats perm_flags as the set of register type flags that a kptr field permits. Adding MEM_PERCPU to that set for BPF_KPTR_PERCPU does not require the source register to carry it, however. The subset test consequently accepts both a plain bpf_obj_new() allocation and a referenced kernel pointer into a __percpu_kptr map field. Loads from the field are always marked MEM_PERCPU. Consumers then treat the stored value as the cookie returned by bpf_percpu_obj_new(): per-CPU pointer helpers relocate it, and map teardown selects the per-CPU free path. A plain allocation can therefore provide an arbitrary kernel read/write, while a kernel pointer can be relocated into an invalid address or sent through a missing destructor. Require the source MEM_PERCPU flag to match the destination field kind. This preserves valid bpf_percpu_obj_new() stores and rejects both the program-BTF and kernel-BTF variants.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-25 11:17:32.663000

Last modified

2026-10-19 10:17:57.823000

View original CVE JSON

{
  "id": "CVE-2026-98039",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-25T11:17:32.663",
  "lastModified": "2026-10-19T10:17:57.823",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require MEM_PERCPU for percpu kptr stores\n\nmap_kptr_match_type() treats perm_flags as the set of register type flags\nthat a kptr field permits. Adding MEM_PERCPU to that set for\nBPF_KPTR_PERCPU does not require the source register to carry it, however.\nThe subset test consequently accepts both a plain bpf_obj_new() allocation\nand a referenced kernel pointer into a __percpu_kptr map field.\n\nLoads from the field are always marked MEM_PERCPU. Consumers then treat the\nstored value as the cookie returned by bpf_percpu_obj_new(): per-CPU pointer\nhelpers relocate it, and map teardown selects the per-CPU free path. A plain\nallocation can therefore provide an arbitrary kernel read/write, while a\nkernel pointer can be relocated into an invalid address or sent through a\nmissing destructor.\n\nRequire the source MEM_PERCPU flag to match the destination field kind.\nThis preserves valid bpf_percpu_obj_new() stores and rejects both the\nprogram-BTF and kernel-BTF variants."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "36d8bdf75a93190e5669b9d1d95994e13e15ba1d",
              "lessThan": "aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "36d8bdf75a93190e5669b9d1d95994e13e15ba1d",
              "lessThan": "0bdd6121c8dd5f1764efe701ce26bb8e15acb172",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "36d8bdf75a93190e5669b9d1d95994e13e15ba1d",
              "lessThan": "ad4ebae5dbc2d47b544aa54f03c12490065be08a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "36d8bdf75a93190e5669b9d1d95994e13e15ba1d",
              "lessThan": "048029ba1c793f8cabc4ad5eea765da01903f8f1",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.7",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.7",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.111",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.7",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/048029ba1c793f8cabc4ad5eea765da01903f8f1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/0bdd6121c8dd5f1764efe701ce26bb8e15acb172",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/aaa9cf7707d1c5c0d2ca9d40c8b71652ac1c3c3f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ad4ebae5dbc2d47b544aa54f03c12490065be08a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}