CVE-2026-98023Hinoki check available

Host crash via VXLAN FDB list corruption

Published Sep 25, 2026 · Updated Sep 25, 2026

Use-after-free in Linux kernel VXLAN from 5.8 allows local users to crash the host through a dynamic FDB nexthop entry. The driver permits a dynamic FDB entry to reference a nexthop shared by two VXLAN devices, while per-device locking leaves the shared list exposed to concurrent aging and mutation. Creating the state requires administrative network configuration and a user-space control plane; the race corrupts the list during entry deletion and can terminate the host.

CVSS severityUnavailable
Unscored
EPSS probability0.13%
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 VXLAN from 5.8 allows local users to crash the host through a dynamic FDB nexthop entry. The driver permits a dynamic FDB entry to reference a nexthop shared by two VXLAN devices, while per-device locking leaves the shared list exposed to concurrent aging and mutation. Creating the state requires administrative network configuration and a user-space control plane; the race corrupts the list during entry deletion and can terminate the host.

The record

CVE
CVE-2026-98023
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
local
Privileges
admin

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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <28f86eec851b7406a4bc6143f82aeba2882d9842
  2. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <3fa64d86fc64eda104e3e97721a12a42a2fd2073
  3. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <53359916ceb649b7e6947c8c2f669368a41c1354
  4. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <98fc57d167446b95b4e719815fe79edef93f8e7a
  5. Affected versionversion=5.8

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <28f86eec851b7406a4bc6143f82aeba2882d9842; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <3fa64d86fc64eda104e3e97721a12a42a2fd2073; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <53359916ceb649b7e6947c8c2f669368a41c1354; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <98fc57d167446b95b4e719815fe79edef93f8e7a; version=5.8

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

T1499Endpoint Denial of Service

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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Your stack

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