CVE-2026-72405

Local denial of service via workqueue race

Published Aug 15, 2026 · Updated Aug 15, 2026

Use-after-free in the Linux kernel allows local users to interrupt service during concurrent UDP tunnel device operations. After the workqueue clears its pending bit, a second queue operation can be mislabeled inactive, letting udp_tunnel_nic_unregister free a structure still queued. Exploitation requires local access and a device-operation race; published analysis confirms denial of service but leaves other behavior undefined.

CVSS severity7.8
High
EPSS probability0.13%
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 the Linux kernel allows local users to interrupt service during concurrent UDP tunnel device operations. After the workqueue clears its pending bit, a second queue operation can be mislabeled inactive, letting udp_tunnel_nic_unregister free a structure still queued. Exploitation requires local access and a device-operation race; published analysis confirms denial of service but leaves other behavior undefined.

The record

CVE
CVE-2026-72405
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, CWE-366
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=5.9
  2. Affected versionversion=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <54292b167466cdf42176b7b6f01da66c184deb12
  3. Affected versionversion=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7
  4. Affected versionversion=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <cee6688e5731c0591643521716d1a1a5c1a98bf8
  5. Affected versionversion=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <ecf69d4b43370c587e48d4d70289dbdb7e039d4d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.9; version=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <54292b167466cdf42176b7b6f01da66c184deb12; version=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7; version=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <cee6688e5731c0591643521716d1a1a5c1a98bf8; version=cc4e3835eff474aa274d6e1d18f69d9d296d3b76 <ecf69d4b43370c587e48d4d70289dbdb7e039d4d

Published CVSS scores

7.0Red HatCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
6.4Amazon LinuxCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
7.8CVE.orgCVSS: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

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

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

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
CWE-366Race Condition within a Thread

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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