CVE-2026-98251 (GCVE-0-2026-98251)

Vulnerability from cvelistv5 – Published: 2026-10-06 08:45 – Updated: 2026-10-07 06:49
VLAI
Title
openvswitch: avoid reallocating confirmed conntrack labels
Summary
In the Linux kernel, the following vulnerability has been resolved: openvswitch: avoid reallocating confirmed conntrack labels ovs_ct_get_conn_labels() adds the labels extension when a conntrack entry does not have one. Confirmed conntracks can be read locklessly, so adding an extension may reallocate and free the extension block while another CPU accesses it. Only add the extension for unconfirmed conntracks. A confirmed conntrack without labels now fails the caller's label operation instead of reallocating its extension storage.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 54/100 over 6619 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 4371d79ea74407fb992c985b1f94391e35bb8289 (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 7ff688aceada1160331a789385ea146f62fbddf7 (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 05eab8dced6bf4d3009a6eeee16ddac99047dc83 (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 579d87ec1e1e85729a6cb2c25961e58beb78640c (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 2e6dd889c325abf23821e1459c3ffef59b7f0009 (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < d16f089bd700f45d720ce989d5495e1dc3be0cf8 (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 8c9fcc6c33950d3db551af664d1fd3d998bfee56 (git)
Affected: c2ac667358708d7cce64c78f58af6adf4c1e848b , < 3f118c8217c109fd13ca61caa301d72c483897ef (git)
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Linux Linux Affected: 4.3
Unaffected: 0 , < 4.3 (semver)
Unaffected: 5.10.271 , ≤ 5.10.* (semver)
Unaffected: 5.15.222 , ≤ 5.15.* (semver)
Unaffected: 6.1.189 , ≤ 6.1.* (semver)
Unaffected: 6.6.158 , ≤ 6.6.* (semver)
Unaffected: 6.12.112 , ≤ 6.12.* (semver)
Unaffected: 6.18.54 , ≤ 6.18.* (semver)
Unaffected: 7.2.8 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc4 , ≤ * (original_commit_for_fix)
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: avoid reallocating confirmed conntrack labels\n\novs_ct_get_conn_labels() adds the labels extension when a conntrack\nentry does not have one.  Confirmed conntracks can be read locklessly,\nso adding an extension may reallocate and free the extension block\nwhile another CPU accesses it.\n\nOnly add the extension for unconfirmed conntracks.  A confirmed\nconntrack without labels now fails the caller\u0027s label operation instead\nof reallocating its extension storage."
          }
        ],
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                "confidentialityImpact": "HIGH",
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                "privilegesRequired": "LOW",
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        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
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      "current_release_date": "2026-10-10T17:32:28+00:00",
      "cve": "CVE-2026-98251",
      "id": "CVE-2026-98251",
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      "product_status:known_affected": "263",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: openvswitch: avoid reallocating confirmed conntrack labels",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98251.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-10-09T16:53:35Z",
      "cve": "CVE-2026-98251",
      "id": "CVE-2026-98251",
      "initial_release_date": "2026-10-09T16:53:35Z",
      "product_status:known_affected": "343",
      "product_status:known_not_affected": "4",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-98251",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-98251.json",
      "version": "2"
    }
  }
}



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Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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

Sightings and recorded dates, grouped by day · UTC

JSON

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.