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UBUNTU-CVE-2026-98856 (CVE-2026-98856)

Vulnerability from osv_ubuntu – Published: 2026-10-18 16:17 – Updated: 2026-10-30 19:02 – Source website

Details

In the Linux kernel, the following vulnerability has been resolved: kprobes: Skip disarmed probes when checking optkprobe overlap On x86, an optkprobe at A replaces five bytes with a jump. If a disabled probe B is at A+2, get_optimized_kprobe() stops at B when arming a new probe C at A+4. It leaves A optimized: A A+1 A+2 A+3 A+4 A's jump | e9 | d0 | d1 | d2 | d3 | after C | e9 | d0 | d1 | d2 | cc | The INT3 for C overwrites the last byte of A's jump displacement, so execution can jump to the wrong address. B can have prepared optinsns while disarmed, but has no jump to unoptimize. Continue past disarmed and unprepared probes to find the active optimized probe before arming a probe in its jump.

Severity

N/A (UNKNOWN)

low

References

URL

Type

	https://ubuntu.com/security/CVE-2026-98856	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-98856	REPORT
	https://git.kernel.org/stable/c/7a39c732a22ec4a36…	REPORT
	https://git.kernel.org/stable/c/985a568171e7bdba6…	REPORT
	https://git.kernel.org/stable/c/6745fa65f41150454…	REPORT
	https://git.kernel.org/stable/c/526fac219e8b7d336…	REPORT

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CVE-2026-98856 (GCVE-0-2026-98856)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:51 – Updated: 2026-10-30 12:40

Title

kprobes: Skip disarmed probes when checking optkprobe overlap

Summary

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6848 records in the last 180 days details

References

8 references

URL	Tags
https://git.kernel.org/stable/c/e29e819cacfb4e3cd…
https://git.kernel.org/stable/c/ab9ed9faa67bf6738…
https://git.kernel.org/stable/c/3b0f604df9e2b9a45…
https://git.kernel.org/stable/c/3f968dcdf01886112…
https://git.kernel.org/stable/c/985a568171e7bdba6…
https://git.kernel.org/stable/c/6745fa65f41150454…
https://git.kernel.org/stable/c/526fac219e8b7d336…
https://git.kernel.org/stable/c/7a39c732a22ec4a36…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < e29e819cacfb4e3cd56d41eb704ab4718d6d2915 (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < ab9ed9faa67bf67383ff7e1479655e232a843c2b (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < 3b0f604df9e2b9a456f1ae5266a439998c4c8826 (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < 3f968dcdf018861129f97910fa7bd680d939a9b0 (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < 985a568171e7bdba6dcde3420d0e5bb515813457 (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < 6745fa65f4115045431c0c15610e876855a04625 (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < 526fac219e8b7d3369b43026bd0a1df51b811cd4 (git) Affected: afd66255b9a48f5851326ddae50e2203fbf71dc9 , < 7a39c732a22ec4a369af9e19fbe3d666ec83eec4 (git)
Linux	Linux	Affected: 2.6.34 Unaffected: 0 , < 2.6.34 (semver) Unaffected: 5.10.273 , ≤ 5.10.* (semver) Unaffected: 5.15.224 , ≤ 5.15.* (semver) Unaffected: 6.1.191 , ≤ 6.1.* (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.56 , ≤ 6.18.* (semver) Unaffected: 7.2.10 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
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        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/kprobes.c"
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              "status": "unaffected",
              "version": "0",
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            },
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              "status": "unaffected",
              "version": "5.10.273",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.224",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
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              "versionType": "semver"
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              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.56",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkprobes: Skip disarmed probes when checking optkprobe overlap\n\nOn x86, an optkprobe at A replaces five bytes with a jump. If a disabled\nprobe B is at A+2, get_optimized_kprobe() stops at B when arming a new\nprobe C at A+4. It leaves A optimized:\n\n              A    A+1  A+2  A+3  A+4\n  A\u0027s jump  | e9 | d0 | d1 | d2 | d3 |\n  after C   | e9 | d0 | d1 | d2 | cc |\n\nThe INT3 for C overwrites the last byte of A\u0027s jump displacement, so\nexecution can jump to the wrong address. B can have prepared optinsns\nwhile disarmed, but has no jump to unoptimize.\n\nContinue past disarmed and unprepared probes to find the active optimized\nprobe before arming a probe in its jump."
        }
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      "providerMetadata": {
        "dateUpdated": "2026-10-30T12:40:17.396Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
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        {
          "url": "https://git.kernel.org/stable/c/7a39c732a22ec4a369af9e19fbe3d666ec83eec4"
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      "title": "kprobes: Skip disarmed probes when checking optkprobe overlap",
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    "datePublished": "2026-10-18T15:51:12.359Z",
    "dateReserved": "2026-09-25T10:25:14.376Z",
    "dateUpdated": "2026-10-30T12:40:17.396Z",
    "state": "PUBLISHED"
  },
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

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