perf/core: Check kernel access when kernel callchains are requested

{
  "id": "1e2aea06d498d8b167f4aeb89a7d785cdb472aaca90ec4d552a1ac0902422681",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-98937",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "perf/core: Check kernel access when kernel callchains are requested",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: perf/core: Check kernel access when kernel callchains are requested perf_event_open() currently gates perf_allow_kernel() only on !attr.exclude_kernel. However, users can still request kernel callchain collection with attr.exclude_callchain_kernel == 0 even when attr.exclude_kernel == 1. That still requires kernel profiling privilege, but the existing check does not enforce it. Update the permission check to call perf_allow_kernel() when either kernel sampling is requested or kernel callchains are requested. This keeps permission checks aligned with requested data and prevents unprivileged use of kernel callchain capture.",
    "evidence": "cve:CVE-2026-98937",
    "products": [
      {
        "name": {
          "value": "Linux",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      },
      {
        "name": {
          "value": "Linux",
          "evidence": "/containers/cna/affected/1/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-98937",
      "aliases": [
        "CVE-2026-98937"
      ],
      "metrics": [],
      "affected": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "0764771dab80d7b84b9a271bee7f1b21a04a3f0c",
              "lessThan": "132bee76097be421ab3012130b5b506324cf2be1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0764771dab80d7b84b9a271bee7f1b21a04a3f0c",
              "lessThan": "2581b43e162cfc43e6f5d8dd8d2b38f3441550de",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0764771dab80d7b84b9a271bee7f1b21a04a3f0c",
              "lessThan": "6e187281f978a2bff98ead6aa40f8ddc9a2c9afb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0764771dab80d7b84b9a271bee7f1b21a04a3f0c",
              "lessThan": "a4573a3838ae4fc73b70019cfa1dac9aaea7cc2f",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "kernel/events/core.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.31"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "2.6.31",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.56",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.2.10",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "kernel/events/core.c"
          ],
          "defaultStatus": "affected"
        }
      ],
      "modified": "2026-10-26T06:56:51.396Z",
      "provider": "cve",
      "references": [
        "https://git.kernel.org/stable/c/132bee76097be421ab3012130b5b506324cf2be1",
        "https://git.kernel.org/stable/c/2581b43e162cfc43e6f5d8dd8d2b38f3441550de",
        "https://git.kernel.org/stable/c/6e187281f978a2bff98ead6aa40f8ddc9a2c9afb",
        "https://git.kernel.org/stable/c/a4573a3838ae4fc73b70019cfa1dac9aaea7cc2f"
      ],
      "provider_metadata": {
        "cna": {
          "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "shortName": "Linux",
          "dateUpdated": "2026-10-26T06:56:51.396Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-98937",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-cve",
  "document_id": 263377,
  "published_at": "2026-10-23T12:11:53.327+00:00"
}