CVE-2026-31508

Kernel crash via premature netdev release

Published Apr 22, 2026 · Updated Apr 22, 2026

Use-after-free in affected Linux Kernel releases allows local users to crash the kernel during Open vSwitch port teardown. ovs_netdev_detach_dev clears IFF_OVS_DATAPATH before unregistering the device, allowing netdev_destroy to queue RCU release and free it while teardown still uses it. Triggering the race requires CAP_NET_ADMIN in the initial network namespace and teardown timing associated with preemption on a real-time kernel.

CVSS severity7.8
High
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in affected Linux Kernel releases allows local users to crash the kernel during Open vSwitch port teardown. ovs_netdev_detach_dev clears IFF_OVS_DATAPATH before unregistering the device, allowing netdev_destroy to queue RCU release and free it while teardown still uses it. Triggering the race requires CAP_NET_ADMIN in the initial network namespace and teardown timing associated with preemption on a real-time kernel.

The record

CVE
CVE-2026-31508
Published
Apr 22, 2026
Updated
Apr 22, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Apr 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 22, 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=052e5db5be4576e0a8ef1460b210da5f328f4cd1 <33609454be4f582e686a4bf13d4482a5ca0f6c4b
  2. Affected versionversion=0fc642f011cb7a7eff41109e66d3b552e9f4d795 <4c3e25a7b711a402fcbbbcfbbdf2868ece1ae7c8
  3. Affected versionversion=5116f61ab11846844585c9082c547c4ccd97ff1a <43579baa17270aa51f93eb09b6e4af6e047b7f6e
  4. Affected versionversion=5498227676303e3ffa9a3a46214af96bc3e81314 <755a6300afbd743cda4b102f24f343380ec0e0ff
  5. Affected versionversion=5498227676303e3ffa9a3a46214af96bc3e81314 <7c770dadfda5cbbde6aa3c4363ed513f1d212bf8
  6. Affected versionversion=6.19
  7. Affected versionversion=b823c3344d5446b720227ba561df10a4f0add515 <df3c95be76103604e752131d9495a24814915ece
  8. Affected versionversion=c98263d5ace597c096a7a60aeef790da7b54979e <5fdeaf591a0942772c2d18ff3563697a49ad01c6
  9. Affected versionversion=f31557fb1b35332cca9994aa196cef284bcf3807 <95265232b49765a4d00f4d028c100bb7185600f4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linux Kernelversion=052e5db5be4576e0a8ef1460b210da5f328f4cd1 <33609454be4f582e686a4bf13d4482a5ca0f6c4b; version=0fc642f011cb7a7eff41109e66d3b552e9f4d795 <4c3e25a7b711a402fcbbbcfbbdf2868ece1ae7c8; version=5116f61ab11846844585c9082c547c4ccd97ff1a <43579baa17270aa51f93eb09b6e4af6e047b7f6e; version=5498227676303e3ffa9a3a46214af96bc3e81314 <755a6300afbd743cda4b102f24f343380ec0e0ff; version=5498227676303e3ffa9a3a46214af96bc3e81314 <7c770dadfda5cbbde6aa3c4363ed513f1d212bf8; version=6.19; version=b823c3344d5446b720227ba561df10a4f0add515 <df3c95be76103604e752131d9495a24814915ece; version=c98263d5ace597c096a7a60aeef790da7b54979e <5fdeaf591a0942772c2d18ff3563697a49ad01c6; version=f31557fb1b35332cca9994aa196cef284bcf3807 <95265232b49765a4d00f4d028c100bb7185600f4

Published CVSS scores

7.8Linux kernel.org CNACVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation

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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