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

Vulnerability from cvelistv5 – Published: 2026-10-23 12:21 – Updated: 2026-10-23 12:21
VLAI
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
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64 (git)
Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 2fb87c6025f90191516bee3ce14b42eb3e1cfed7 (git)
Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < d109141ba14652146089ef78b32d5e4d5285ebad (git)
Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 7931fb9181421953f3133b408b0f2e2b8dd68b61 (git)
Affected: 8266a0491e92d39dc9af739e8380a0daa9b8836b , < 5158353121bae4f552cb677ce8c5c3ef52f93a0d (git)
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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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          "product": "Linux",
          "programFiles": [
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        }
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    "dateReserved": "2026-09-25T10:25:14.387Z",
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        "vulnStatus": "Received"
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  }
}



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