CVE-2026-98540

Status: ReceivedUnscored—
Severity—Unscored
Exploitation probability0.19 %higher than 8% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

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

fprobe: Terminate the fgraph_data list when the reservation is not filled

fprobe_fgraph_entry() reserves shadow stack space for every fprobe with an exit handler, but only fills it for those whose entry handler returns 0. fgraph_reserve_data() does not clear the area, so fprobe_return() parses the unused tail as headers left over from an earlier call, and an exit handler can run twice or despite its entry handler asking to skip it.

Write a zero word after the last entry to terminate the walk. A zeroed slot does not decode to a NULL fprobe on the arches that encode the header into one unsigned long, since arch_decode_fprobe_header_fp() ORs in FPROBE_HEADER_MSB_PATTERN, so make read_fprobe_header() return NULL for a zeroed slot.

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
0.19 %
Percentile among all scored CVEs
8
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.

References

Show 2 references

Raw JSON (NVD)

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{
  "id": "CVE-2026-98540",
  "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": "e0a384434ae1bdfb03954c46c464e3dbd3223ad6",
              "lessThan": "b7459fddcb27a4b7d01067678172afa362cf660d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e0a384434ae1bdfb03954c46c464e3dbd3223ad6",
              "lessThan": "1d653a183973f5283a3db5a38cd5e195eb152244",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "kernel/trace/fprobe.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.2.9",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "kernel/trace/fprobe.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-10-18T16:17:05.863",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1d653a183973f5283a3db5a38cd5e195eb152244",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b7459fddcb27a4b7d01067678172afa362cf660d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfprobe: Terminate the fgraph_data list when the reservation is not filled\n\nfprobe_fgraph_entry() reserves shadow stack space for every fprobe with\nan exit handler, but only fills it for those whose entry handler returns\n0. fgraph_reserve_data() does not clear the area, so fprobe_return()\nparses the unused tail as headers left over from an earlier call, and an\nexit handler can run twice or despite its entry handler asking to skip\nit.\n\nWrite a zero word after the last entry to terminate the walk. A zeroed\nslot does not decode to a NULL fprobe on the arches that encode the\nheader into one unsigned long, since arch_decode_fprobe_header_fp() ORs\nin FPROBE_HEADER_MSB_PATTERN, so make read_fprobe_header() return NULL\nfor a zeroed slot."
    }
  ],
  "lastModified": "2026-10-19T10:19:09.837",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}