CVE-2026-98317

Status: ReceivedUnscored—

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

neighbour: Enforce min/max to NDTPA_INTERVAL_PROBE_TIME_MS.

NDTPA_INTERVAL_PROBE_TIME_MS sets .type and .min but misses .validation_type, so no validation is applied:

Moreover, nla_get_msecs() uses msecs_to_jiffies(), and u64 is silently cast to u32, so a larger value can bypass the min check:

msecs_to_jiffies() returns MAX_JIFFY_OFFSET if the value is larger than INT_MAX. Also, INT_MAX ms overflows int NEIGH_VAR() when HZ > 1000 (Alpha, MIPS), and passing a negative integer to queue_delayed_work(unsigned long delay) causes sign extension, which wraps around the expiry time to the past, resulting in it being handled as 0 delay in the timer wheel.

Read full descriptionShow less

Let's use NLA_POLICY_FULL_RANGE() and limit the max to 1 day.

The same max check is applied to sysctl as well.

Note that this controls the probe interval for NTF_MANAGED entries, so the max of 1 day is unlikely to break any deployments.

Technical details traces, logs and code from the original report

  # ynl --family rt-neigh --do setneightbl \
  --json '{"name": "arp_cache", "parms": {"interval-probe-time-ms": 0}}'

  # ynl --family rt-neigh --dump getneightbl --output-json | \
  jq '.[] | select(.name == "arp_cache" and has("config"))
          | .parms["interval-probe-time-ms"]'
  0

  e.g. 4294967296 == 0x100000000

  # ynl --family rt-neigh --do setneightbl \
  --json '{"name": "arp_cache", "parms": {"interval-probe-time-ms": 4294967296}}'

  # ynl --family rt-neigh --dump getneightbl --output-json | \
  jq '.[] | select(.name == "arp_cache" and has("config"))
          | .parms["interval-probe-time-ms"]'
  0

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: 0.18%
Percentile among all scored CVEs: 7
Score date: 10/6/2026

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

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-98317",
  "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": "211da42eaa45db7b0edfde187dd88a85fbd466b5",
              "lessThan": "982c7f66c04134b77126edbfd8a63ecd6928cfd9",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "211da42eaa45db7b0edfde187dd88a85fbd466b5",
              "lessThan": "8550b50e49b01b572e653e572f24ddd73949aa74",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "211da42eaa45db7b0edfde187dd88a85fbd466b5",
              "lessThan": "6d79b223ec44ada58ad37db42f539b60985a7722",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "Documentation/netlink/specs/rt-neigh.yaml",
            "Documentation/networking/ip-sysctl.rst",
            "net/core/neighbour.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.0"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.18.54",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.2.8",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3-rc4",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "Documentation/netlink/specs/rt-neigh.yaml",
            "Documentation/networking/ip-sysctl.rst",
            "net/core/neighbour.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-10-06T09:18:23.530",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/6d79b223ec44ada58ad37db42f539b60985a7722",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8550b50e49b01b572e653e572f24ddd73949aa74",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/982c7f66c04134b77126edbfd8a63ecd6928cfd9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nneighbour: Enforce min/max to NDTPA_INTERVAL_PROBE_TIME_MS.\n\nNDTPA_INTERVAL_PROBE_TIME_MS sets .type and .min but misses\n.validation_type, so no validation is applied:\n\n  # ynl --family rt-neigh --do setneightbl \\\n  --json '{\"name\": \"arp_cache\", \"parms\": {\"interval-probe-time-ms\": 0}}'\n\n  # ynl --family rt-neigh --dump getneightbl --output-json | \\\n  jq '.[] | select(.name == \"arp_cache\" and has(\"config\"))\n          | .parms[\"interval-probe-time-ms\"]'\n  0\n\nMoreover, nla_get_msecs() uses msecs_to_jiffies(), and u64 is\nsilently cast to u32, so a larger value can bypass the min check:\n\n  e.g. 4294967296 == 0x100000000\n\n  # ynl --family rt-neigh --do setneightbl \\\n  --json '{\"name\": \"arp_cache\", \"parms\": {\"interval-probe-time-ms\": 4294967296}}'\n\n  # ynl --family rt-neigh --dump getneightbl --output-json | \\\n  jq '.[] | select(.name == \"arp_cache\" and has(\"config\"))\n          | .parms[\"interval-probe-time-ms\"]'\n  0\n\nmsecs_to_jiffies() returns MAX_JIFFY_OFFSET if the value is\nlarger than INT_MAX.  Also, INT_MAX ms overflows int NEIGH_VAR()\nwhen HZ > 1000 (Alpha, MIPS), and passing a negative integer to\nqueue_delayed_work(unsigned long delay) causes sign extension,\nwhich wraps around the expiry time to the past, resulting in it\nbeing handled as 0 delay in the timer wheel.\n\nLet's use NLA_POLICY_FULL_RANGE() and limit the max to 1 day.\n\nThe same max check is applied to sysctl as well.\n\nNote that this controls the probe interval for NTF_MANAGED\nentries, so the max of 1 day is unlikely to break any\ndeployments."
    }
  ],
  "lastModified": "2026-10-06T09:18:23.530",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}