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7.8
HIGH CVSS 3.1
CVE-2026-74262
kcm: use WRITE_ONCE() when changing lower socket callbacks
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: kcm: use WRITE_ONCE() when changing lower socket callbacks kcm_attach() replaces a live lower TCP socket's sk_data_ready and sk_write_space callbacks with KCM handlers, and kcm_unattach() restores them later. Those callback-pointer updates are still plain stores even though the same fields can be read and invoked concurrently on other CPUs. If another CPU observes an older callback snapshot after the live field has already been restored, callback execution can run with a mismatched target and sk_user_data state, leading to stale or misdirected wakeups. Use WRITE_ONCE() for the callback replacement and restore operations so these shared callback fields follow the same visibility contract already established by the earlier 4022 fixes.

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-2026-74262 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
Ensure concurrent CPU access to socket callbacks is synchronized.
  • Update the Linux kernel to the latest version.
  • Apply the fix for WRITE_ONCE() in callback updates.
  • Synchronize shared callback field visibility.
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-2026-74262.

URL Resource
https://git.kernel.org/stable/c/0cb3e2f40679032c1aa2186280a86e5ead0161ee
https://git.kernel.org/stable/c/11faefd11ce2448bac7279ab302dd1954a6547fe
https://git.kernel.org/stable/c/47186409c092cd7dd70350999186c700233e854d
https://git.kernel.org/stable/c/9684fff87124b201e11dea01ded9173025359a0f
https://git.kernel.org/stable/c/b4ccd6eef671d7c44a30123cd29f3acf3de8468e
https://git.kernel.org/stable/c/b8c90823cdfb5f3d22f261aeb3e9066612853c36
https://git.kernel.org/stable/c/f01fb6138f8eb606b56ce9158e2d8b72352c53f4
https://git.kernel.org/stable/c/fa26e4606aed0f7fe793c325506adeda1d847a43
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-74262 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-2026-74262 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-2026-74262 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-2026-74262 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': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '0cb3e2f40679032c1aa2186280a86e5ead0161ee', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'fa26e4606aed0f7fe793c325506adeda1d847a43', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'b4ccd6eef671d7c44a30123cd29f3acf3de8468e', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'b8c90823cdfb5f3d22f261aeb3e9066612853c36', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '11faefd11ce2448bac7279ab302dd1954a6547fe', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'f01fb6138f8eb606b56ce9158e2d8b72352c53f4', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '9684fff87124b201e11dea01ded9173025359a0f', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '47186409c092cd7dd70350999186c700233e854d', 'versionType': 'git'}], 'programFiles': ['net/kcm/kcmsock.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'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/kcm/kcmsock.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '0cb3e2f40679032c1aa2186280a86e5ead0161ee', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'fa26e4606aed0f7fe793c325506adeda1d847a43', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'b4ccd6eef671d7c44a30123cd29f3acf3de8468e', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'b8c90823cdfb5f3d22f261aeb3e9066612853c36', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '11faefd11ce2448bac7279ab302dd1954a6547fe', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'f01fb6138f8eb606b56ce9158e2d8b72352c53f4', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '9684fff87124b201e11dea01ded9173025359a0f', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '47186409c092cd7dd70350999186c700233e854d', 'versionType': 'git'}], 'programFiles': ['net/kcm/kcmsock.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'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/kcm/kcmsock.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': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '0cb3e2f40679032c1aa2186280a86e5ead0161ee', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'fa26e4606aed0f7fe793c325506adeda1d847a43', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'b4ccd6eef671d7c44a30123cd29f3acf3de8468e', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'b8c90823cdfb5f3d22f261aeb3e9066612853c36', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '11faefd11ce2448bac7279ab302dd1954a6547fe', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': 'f01fb6138f8eb606b56ce9158e2d8b72352c53f4', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '9684fff87124b201e11dea01ded9173025359a0f', 'versionType': 'git'}, {'status': 'affected', 'version': 'ab7ac4eb9832e32a09f4e8042705484d2fb0aad3', 'lessThan': '47186409c092cd7dd70350999186c700233e854d', 'versionType': 'git'}], 'programFiles': ['net/kcm/kcmsock.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'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/kcm/kcmsock.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: kcm: use WRITE_ONCE() when changing lower socket callbacks kcm_attach() replaces a live lower TCP socket's sk_data_ready and sk_write_space callbacks with KCM handlers, and kcm_unattach() restores them later. Those callback-pointer updates are still plain stores even though the same fields can be read and invoked concurrently on other CPUs. If another CPU observes an older callback snapshot after the live field has already been restored, callback execution can run with a mismatched target and sk_user_data state, leading to stale or misdirected wakeups. Use WRITE_ONCE() for the callback replacement and restore operations so these shared callback fields follow the same visibility contract already established by the earlier 4022 fixes.
    Added Reference https://git.kernel.org/stable/c/0cb3e2f40679032c1aa2186280a86e5ead0161ee
    Added Reference https://git.kernel.org/stable/c/11faefd11ce2448bac7279ab302dd1954a6547fe
    Added Reference https://git.kernel.org/stable/c/47186409c092cd7dd70350999186c700233e854d
    Added Reference https://git.kernel.org/stable/c/9684fff87124b201e11dea01ded9173025359a0f
    Added Reference https://git.kernel.org/stable/c/b4ccd6eef671d7c44a30123cd29f3acf3de8468e
    Added Reference https://git.kernel.org/stable/c/b8c90823cdfb5f3d22f261aeb3e9066612853c36
    Added Reference https://git.kernel.org/stable/c/f01fb6138f8eb606b56ce9158e2d8b72352c53f4
    Added Reference https://git.kernel.org/stable/c/fa26e4606aed0f7fe793c325506adeda1d847a43
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
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Scope
Confidentiality Impact
Integrity Impact
Availability Impact