Vulnerability-Lookup

GHSA-C83G-Q254-QMXR

Vulnerability from github – Published: 2026-10-23 15:31 – Updated: 2026-10-23 15:31

Details

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

net: bridge: avoid recursive multicast port cleanup

br_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL port groups by calling br_multicast_del_pg(). For S,G entries, that deletion calls back into br_multicast_sg_del_exclude_ports(), so a large number of STAR_EXCL ports consumes one kernel stack frame per port and can hit the stack guard page.

Keep the complete port-group deletion path for cleanup, but suppress the S,G exclude-port cleanup while that helper is already walking the same entry. Normal deletion callers retain the existing behavior.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-99031"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-23T13:17:26Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: avoid recursive multicast port cleanup\n\nbr_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL\nport groups by calling br_multicast_del_pg(). For S,G entries, that\ndeletion calls back into br_multicast_sg_del_exclude_ports(), so a large\nnumber of STAR_EXCL ports consumes one kernel stack frame per port and can\nhit the stack guard page.\n\nKeep the complete port-group deletion path for cleanup, but suppress the\nS,G exclude-port cleanup while that helper is already walking the same\nentry. Normal deletion callers retain the existing behavior.",
  "id": "GHSA-c83g-q254-qmxr",
  "modified": "2026-10-23T15:31:35Z",
  "published": "2026-10-23T15:31:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99031"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2fb87c6025f90191516bee3ce14b42eb3e1cfed7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5158353121bae4f552cb677ce8c5c3ef52f93a0d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7931fb9181421953f3133b408b0f2e2b8dd68b61"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d109141ba14652146089ef78b32d5e4d5285ebad"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-99031 (GCVE-0-2026-99031)

Vulnerability from cvelistv5 – Published: 2026-10-23 12:21 – Updated: 2026-10-23 12:21

Title

net: bridge: avoid recursive multicast port cleanup

Summary

In the Linux kernel, the following vulnerability has been resolved: net: bridge: avoid recursive multicast port cleanup br_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL port groups by calling br_multicast_del_pg(). For S,G entries, that deletion calls back into br_multicast_sg_del_exclude_ports(), so a large number of STAR_EXCL ports consumes one kernel stack frame per port and can hit the stack guard page. Keep the complete port-group deletion path for cleanup, but suppress the S,G exclude-port cleanup while that helper is already walking the same entry. Normal deletion callers retain the existing behavior.

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7056 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/695a5a4c69c922d92…
https://git.kernel.org/stable/c/2fb87c6025f901915…
https://git.kernel.org/stable/c/d109141ba14652146…
https://git.kernel.org/stable/c/7931fb9181421953f…
https://git.kernel.org/stable/c/5158353121bae4f55…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64 (git) Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 2fb87c6025f90191516bee3ce14b42eb3e1cfed7 (git) Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < d109141ba14652146089ef78b32d5e4d5285ebad (git) Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 7931fb9181421953f3133b408b0f2e2b8dd68b61 (git) Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 5158353121bae4f552cb677ce8c5c3ef52f93a0d (git)
Linux	Linux	Affected: 5.10 Unaffected: 0 , < 5.10 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.57 , ≤ 6.18.* (semver) Unaffected: 7.2.11 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

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JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/bridge/br_multicast.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
              "version": "8266a0491e92d39dc9af739e8380a0daa9b8836b",
              "versionType": "git"
            },
            {
              "lessThan": "2fb87c6025f90191516bee3ce14b42eb3e1cfed7",
              "status": "affected",
              "version": "8266a0491e92d39dc9af739e8380a0daa9b8836b",
              "versionType": "git"
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            {
              "lessThan": "d109141ba14652146089ef78b32d5e4d5285ebad",
              "status": "affected",
              "version": "8266a0491e92d39dc9af739e8380a0daa9b8836b",
              "versionType": "git"
            },
            {
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              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "5158353121bae4f552cb677ce8c5c3ef52f93a0d",
              "status": "affected",
              "version": "8266a0491e92d39dc9af739e8380a0daa9b8836b",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/bridge/br_multicast.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "status": "affected",
              "version": "5.10"
            },
            {
              "lessThan": "5.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
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            {
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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": "6.18.57",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
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      "providerMetadata": {
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    "datePublished": "2026-10-23T12:21:31.535Z",
    "dateReserved": "2026-09-25T10:25:14.387Z",
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    "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.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
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