CVE-2026-98540 (GCVE-0-2026-98540)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:18 – Updated: 2026-10-19 09:21
VLAI
Title
fprobe: Terminate the fgraph_data list when the reservation is not filled
Summary
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.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7033 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e0a384434ae1bdfb03954c46c464e3dbd3223ad6 , < b7459fddcb27a4b7d01067678172afa362cf660d (git)
Affected: e0a384434ae1bdfb03954c46c464e3dbd3223ad6 , < 1d653a183973f5283a3db5a38cd5e195eb152244 (git)
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Linux Linux Affected: 7.1
Unaffected: 0 , < 7.1 (semver)
Unaffected: 7.2.9 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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          "programFiles": [
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T09:21:23.633Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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    "cveId": "CVE-2026-98540",
    "datePublished": "2026-10-18T15:18:08.352Z",
    "dateReserved": "2026-09-25T10:25:14.356Z",
    "dateUpdated": "2026-10-19T09:21:23.633Z",
    "state": "PUBLISHED"
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          {
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            "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."
          }
        ],
        "id": "CVE-2026-98540",
        "lastModified": "2026-10-19T10:19:09.837",
        "metrics": {},
        "published": "2026-10-18T16:17:05.863",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      "product_status:known_not_affected": "277",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: fprobe: Terminate the fgraph_data list when the reservation is not filled",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98540.json",
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      "cve": "CVE-2026-98540",
      "id": "CVE-2026-98540",
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      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2026/cve-2026-98540.json",
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    }
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}



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