CVE-2026-98631

Status: ReceivedUnscored—

Severity—Unscored

Exploitation probability0.21 %higher than 11% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitNot knownno public code found

In the Linux kernel, the following vulnerability has been resolved:

xsk: Use a 32-bit compare in xsk_map_gen_lookup

xsk_map_gen_lookup() loads a u32 key and compares it with max_entries using BPF_JMP_IMM. BPF immediates are sign-extended to 64 bits, so a max_entries value of 0x80000000 or higher becomes a threshold larger than every zero-extended 32-bit key. An out-of-range index then skips the bounds check and the generated lookup reads past xsk_map[].

Compare with BPF_JMP32_IMM so the check stays in 32-bit unsigned range.

CVSS

NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.21 %
Percentile among all scored CVEs: 11
Score date: 10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Linux — Linux Kernel^AI

References

Show 8 references

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-98631",
  "cveTags": [],
  "metrics": {},
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "c6d5c582d55a8f229d75e98d62eaa065b0deb18d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "227ec890559e922e235eb543646e3bf0bd8269b0",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "11d9be35c1f4233798e99be98bc474f83a254c6c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "123f90f394ca404ab8796a7c8072ff7fa5b65a9c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "36461e58f88a1b723f86693f437ac12e60ff4363",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "b5c0cff0c5331582ab01c4c423731453a8381acc",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e65650f291ee72fc578d6346080fc4699204ef2c",
              "lessThan": "70504de0bb627848667207bec7ccfd647deb8814",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "net/xdp/xskmap.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.5"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.5",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.271",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.222",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.189",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.158",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.112",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.55",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.2.9",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "net/xdp/xskmap.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-10-18T16:17:16.180",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/11d9be35c1f4233798e99be98bc474f83a254c6c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/123f90f394ca404ab8796a7c8072ff7fa5b65a9c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/227ec890559e922e235eb543646e3bf0bd8269b0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/36461e58f88a1b723f86693f437ac12e60ff4363",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/70504de0bb627848667207bec7ccfd647deb8814",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b5c0cff0c5331582ab01c4c423731453a8381acc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c6d5c582d55a8f229d75e98d62eaa065b0deb18d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxsk: Use a 32-bit compare in xsk_map_gen_lookup\n\nxsk_map_gen_lookup() loads a u32 key and compares it with max_entries\nusing BPF_JMP_IMM. BPF immediates are sign-extended to 64 bits, so a\nmax_entries value of 0x80000000 or higher becomes a threshold larger\nthan every zero-extended 32-bit key. An out-of-range index then skips\nthe bounds check and the generated lookup reads past xsk_map[].\n\nCompare with BPF_JMP32_IMM so the check stays in 32-bit unsigned range."
    }
  ],
  "lastModified": "2026-10-19T10:19:27.347",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}