0.0
NA
CVE-2026-64138
ksmbd: validate SID in parent security descriptor during ACL inheritance
Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate SID in parent security descriptor during ACL inheritance Introduce smb_validate_ntsd_sid() helper to safely validate Owner SID and Group SID inside the NT Security Descriptor (smb_ntsd) retrieved from the parent directory.

INFO

Published Date :

July 19, 2026, 4:17 p.m.

Last Modified :

July 20, 2026, 7:16 a.m.

Remotely Exploit :

No

Source :

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

The following products are affected by CVE-2026-64138 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.

No affected product recoded yet

Solution
Validate security identifiers in kernel SMB module to prevent authorization bypass.
  • Update the Linux kernel to include the security fix.
  • Apply the patch for ksmbd to validate SIDs.
  • Ensure proper access controls are configured.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-64138 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-2026-64138 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-2026-64138 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-64138 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

    Jul. 20, 2026

    Action Type Old Value New Value
    Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': 'f0e5c9c663badc9982e6941322eef1cb17de0f11', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '18d8db24b0a5b7be4829238dd4022236df02d421', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '1c9d0646a9959752f11ca1080dc1ff26bd1756cb', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '69f030cf95488ae1186c72ac8c66fd279664ea7f', 'versionType': 'git'}, {'status': 'affected', 'version': '0', 'lessThan': '6.12.92', 'versionType': 'semver'}, {'status': 'affected', 'version': '0', 'lessThan': '6.18.34', 'versionType': 'semver'}, {'status': 'affected', 'version': '0', 'lessThan': '7.0.11', 'versionType': 'semver'}], 'programFiles': ['fs/smb/server/smbacl.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/server/smbacl.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': 'f0e5c9c663badc9982e6941322eef1cb17de0f11', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '18d8db24b0a5b7be4829238dd4022236df02d421', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '1c9d0646a9959752f11ca1080dc1ff26bd1756cb', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '69f030cf95488ae1186c72ac8c66fd279664ea7f', 'versionType': 'git'}], 'programFiles': ['fs/smb/server/smbacl.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.15'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.15', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/server/smbacl.c'], 'defaultStatus': 'affected'}]
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 19, 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': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': 'f0e5c9c663badc9982e6941322eef1cb17de0f11', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '18d8db24b0a5b7be4829238dd4022236df02d421', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '1c9d0646a9959752f11ca1080dc1ff26bd1756cb', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '69f030cf95488ae1186c72ac8c66fd279664ea7f', 'versionType': 'git'}, {'status': 'affected', 'version': '0', 'lessThan': '6.12.92', 'versionType': 'semver'}, {'status': 'affected', 'version': '0', 'lessThan': '6.18.34', 'versionType': 'semver'}, {'status': 'affected', 'version': '0', 'lessThan': '7.0.11', 'versionType': 'semver'}], 'programFiles': ['fs/smb/server/smbacl.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/server/smbacl.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate SID in parent security descriptor during ACL inheritance Introduce smb_validate_ntsd_sid() helper to safely validate Owner SID and Group SID inside the NT Security Descriptor (smb_ntsd) retrieved from the parent directory.
    Added Reference https://git.kernel.org/stable/c/18d8db24b0a5b7be4829238dd4022236df02d421
    Added Reference https://git.kernel.org/stable/c/1c9d0646a9959752f11ca1080dc1ff26bd1756cb
    Added Reference https://git.kernel.org/stable/c/69f030cf95488ae1186c72ac8c66fd279664ea7f
    Added Reference https://git.kernel.org/stable/c/f0e5c9c663badc9982e6941322eef1cb17de0f11
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.