1. Home
  2. Vulnerabilities
  3. CVE-2026-72405
7.8
HIGH CVSS 3.1
CVE-2026-72405
net: udp_tunnel: prevent double queueing in udp_tunnel_nic_device_sync
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: net: udp_tunnel: prevent double queueing in udp_tunnel_nic_device_sync Yue Sun reported a use-after-free and debugobjects warning in udp_tunnel_nic_device_sync_work() during concurrent device operations. The workqueue core clears the internal pending bit before invoking the worker. At that point, a concurrent thread can queue the work again. When the already running worker eventually clears the work_pending flag to 0, it mistakenly clears the flag for the newly queued instance. udp_tunnel_nic_unregister() then observes work_pending as 0 and frees the structure while the second work item is still active in the queue, leading to UAF. Fix this by returning early in udp_tunnel_nic_device_sync() if work_pending is already set, preventing redundant work queueing.

Details
INFO

Published Date :

Aug. 15, 2026, 6:22 a.m.

Last Modified :

Aug. 17, 2026, 6:19 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-72405 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Fix a use-after-free in UDP tunnel device sync by preventing double queueing.
  • Update the Linux kernel to the latest version.
  • Apply the provided patch for UDP tunnel device sync.
  • Review concurrent device operation handling.
  • Test for race conditions in workqueue logic.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-72405.

URL Resource
https://git.kernel.org/stable/c/54292b167466cdf42176b7b6f01da66c184deb12
https://git.kernel.org/stable/c/9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7
https://git.kernel.org/stable/c/cee6688e5731c0591643521716d1a1a5c1a98bf8
https://git.kernel.org/stable/c/ecf69d4b43370c587e48d4d70289dbdb7e039d4d
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-72405 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-72405 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-72405 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-72405 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Aug. 17, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': 'cee6688e5731c0591643521716d1a1a5c1a98bf8', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': '9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': '54292b167466cdf42176b7b6f01da66c184deb12', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': 'ecf69d4b43370c587e48d4d70289dbdb7e039d4d', 'versionType': 'git'}], 'programFiles': ['net/ipv4/udp_tunnel_nic.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.9'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.9', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/ipv4/udp_tunnel_nic.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': 'cee6688e5731c0591643521716d1a1a5c1a98bf8', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': '9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': '54292b167466cdf42176b7b6f01da66c184deb12', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': 'ecf69d4b43370c587e48d4d70289dbdb7e039d4d', 'versionType': 'git'}], 'programFiles': ['net/ipv4/udp_tunnel_nic.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.9'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.9', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/ipv4/udp_tunnel_nic.c'], 'defaultStatus': 'affected'}]
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Aug. 15, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': 'cee6688e5731c0591643521716d1a1a5c1a98bf8', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': '9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': '54292b167466cdf42176b7b6f01da66c184deb12', 'versionType': 'git'}, {'status': 'affected', 'version': 'cc4e3835eff474aa274d6e1d18f69d9d296d3b76', 'lessThan': 'ecf69d4b43370c587e48d4d70289dbdb7e039d4d', 'versionType': 'git'}], 'programFiles': ['net/ipv4/udp_tunnel_nic.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.9'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.9', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/ipv4/udp_tunnel_nic.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: net: udp_tunnel: prevent double queueing in udp_tunnel_nic_device_sync Yue Sun reported a use-after-free and debugobjects warning in udp_tunnel_nic_device_sync_work() during concurrent device operations. The workqueue core clears the internal pending bit before invoking the worker. At that point, a concurrent thread can queue the work again. When the already running worker eventually clears the work_pending flag to 0, it mistakenly clears the flag for the newly queued instance. udp_tunnel_nic_unregister() then observes work_pending as 0 and frees the structure while the second work item is still active in the queue, leading to UAF. Fix this by returning early in udp_tunnel_nic_device_sync() if work_pending is already set, preventing redundant work queueing.
    Added Reference https://git.kernel.org/stable/c/54292b167466cdf42176b7b6f01da66c184deb12
    Added Reference https://git.kernel.org/stable/c/9075efb9b2c1d9d7a8285c937b64aa93ca0c41b7
    Added Reference https://git.kernel.org/stable/c/cee6688e5731c0591643521716d1a1a5c1a98bf8
    Added Reference https://git.kernel.org/stable/c/ecf69d4b43370c587e48d4d70289dbdb7e039d4d
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact