CVE-2026-98026Hinoki check available

Unsafe kernel memory access via premature port-group release

Published Sep 25, 2026 · Updated Sep 25, 2026

Use-after-free in Linux kernel bridge multicast handling allows attackers to access a freed port-group object during concurrent list traversal. br_multicast_del_port_group removes an mglist node without an RCU-safe helper and frees it immediately, while br_multicast_list_adjacent can still follow that node. Reachability requires bridge multicast port-group teardown to overlap the RCU reader; public material does not establish a resulting crash, privilege gain, or data exposure.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Use-after-free in Linux kernel bridge multicast handling allows attackers to access a freed port-group object during concurrent list traversal. br_multicast_del_port_group removes an mglist node without an RCU-safe helper and frees it immediately, while br_multicast_list_adjacent can still follow that node. Reachability requires bridge multicast port-group teardown to overlap the RCU reader; public material does not establish a resulting crash, privilege gain, or data exposure.

The record

CVE
CVE-2026-98026
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <38ab2a435001a3c4dbeb70a52f5921e1ccd66f55
  2. Affected versionversion=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <4b772869a1e5f9da5cef5b9c722ec0aa424ee0a0
  3. Affected versionversion=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <98247c8264d2076f81fa114bdfa2c2271953ac7c
  4. Affected versionversion=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <f7bf57e94a5d6214b87be08486cb33836fbfa573
  5. Affected versionversion=3.16

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <38ab2a435001a3c4dbeb70a52f5921e1ccd66f55; version=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <4b772869a1e5f9da5cef5b9c722ec0aa424ee0a0; version=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <98247c8264d2076f81fa114bdfa2c2271953ac7c; version=07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 <f7bf57e94a5d6214b87be08486cb33836fbfa573; version=3.16

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

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No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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