9.8
CRITICAL CVSS 3.1
CVE-2026-72381
ksmbd: fix use-after-free of fp->owner.name in durable handle owner check
Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of fp->owner.name in durable handle owner check Two concurrent SMB2 durable reconnects (DH2C/DHnC) on the same persistent_id race the fp->owner.name compare-read in ksmbd_vfs_compare_durable_owner() against the kfree() in ksmbd_reopen_durable_fd()'s reopen-success path. fp->owner.name is a standalone kstrdup() buffer whose lifetime is independent of the fp refcount, and the two sites share no lock: the compare reads the buffer while the reopen frees it, so the strcmp() can dereference freed memory. Commit 7ce4fc40018d ("ksmbd: fix durable reconnect double-bind race in ksmbd_reopen_durable_fd") made the fp->conn claim atomic under global_ft.lock (closing the owner.name double-free and the ksmbd_file write-UAF), but the compare-read versus reopen-free pair was left unserialized. BUG: KASAN: slab-use-after-free in strcmp+0x2c/0x80 Read of size 1 by task kworker strcmp ksmbd_vfs_compare_durable_owner smb2_check_durable_oplock smb2_open Freed by task kworker: kfree ksmbd_reopen_durable_fd smb2_open Allocated by task kworker: kstrdup session_fd_check smb2_session_logoff The buggy address belongs to the cache kmalloc-8 Serialize both sides of the race with fp->f_lock. The global durable file-table lock still protects the durable reconnect claim, but fp->owner.name is per-open state and does not need to block unrelated durable table lookups or reconnects. The teardown is left at its existing location after the reopen-success point so that an __open_id() rollback still retains owner.name for a later legitimate reconnect to verify.

INFO

Published Date :

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

Last Modified :

Aug. 17, 2026, 6:18 a.m.

Remotely Exploit :

Yes !

Source :

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

The following products are affected by CVE-2026-72381 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
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 CRITICAL 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Fix a race condition in ksmbd by serializing durable handle owner checks with file structure locks.
  • Serialize owner checks with fp->f_lock.
  • Ensure global durable file-table lock protects reconnect claims.
  • Apply the fix for the durable reconnect double-bind race.
  • Update the Linux kernel to the latest version.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-72381 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-2026-72381 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-2026-72381 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-72381 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:N/AC:L/PR:N/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': '712cdf917e77a6444ce3836874829d770db20ee6', 'lessThan': 'fb978d72052704c6b06c6b0f129fcd60b77169f5', 'versionType': 'git'}, {'status': 'affected', 'version': 'c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d', 'lessThan': '93d4d46bf9d442a12ea87278049ec416962c627f', 'versionType': 'git'}, {'status': 'affected', 'version': '00ce8d6789dae72d042a4522264964c72891ca37', 'lessThan': '5a5ac2852cd326529d02f778bc1aa6184701f4d7', 'versionType': 'git'}, {'status': 'affected', 'version': '49110a8ce654bbe56bef7c5e44cce31f4b102b8a', 'lessThan': 'ed98719be41389d416953b8ef9f07a07dfea6b2b', 'versionType': 'git'}, {'status': 'affected', 'version': '49110a8ce654bbe56bef7c5e44cce31f4b102b8a', 'lessThan': '38637163501fd9e2f684b8cd275d0db5d79f37c6', 'versionType': 'git'}, {'status': 'affected', 'version': 'c908c853f304a4969b5aa10eba0b50350cc65b80', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.142', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.92', 'lessThan': '6.12.97', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.18.25', 'lessThan': '6.18.40', 'versionType': 'semver'}, {'status': 'affected', 'version': '7.0.2', 'lessThan': '7.1', 'versionType': 'semver'}], 'programFiles': ['fs/smb/server/vfs_cache.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '7.1'}, {'status': 'unaffected', 'version': '0', 'lessThan': '7.1', 'versionType': 'semver'}, {'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-rc2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/server/vfs_cache.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '712cdf917e77a6444ce3836874829d770db20ee6', 'lessThan': 'fb978d72052704c6b06c6b0f129fcd60b77169f5', 'versionType': 'git'}, {'status': 'affected', 'version': 'c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d', 'lessThan': '93d4d46bf9d442a12ea87278049ec416962c627f', 'versionType': 'git'}, {'status': 'affected', 'version': '00ce8d6789dae72d042a4522264964c72891ca37', 'lessThan': '5a5ac2852cd326529d02f778bc1aa6184701f4d7', 'versionType': 'git'}, {'status': 'affected', 'version': '49110a8ce654bbe56bef7c5e44cce31f4b102b8a', 'lessThan': 'ed98719be41389d416953b8ef9f07a07dfea6b2b', 'versionType': 'git'}, {'status': 'affected', 'version': '49110a8ce654bbe56bef7c5e44cce31f4b102b8a', 'lessThan': '38637163501fd9e2f684b8cd275d0db5d79f37c6', 'versionType': 'git'}, {'status': 'affected', 'version': 'c908c853f304a4969b5aa10eba0b50350cc65b80', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.142', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.92', 'lessThan': '6.12.97', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.18.25', 'lessThan': '6.18.40', 'versionType': 'semver'}, {'status': 'affected', 'version': '7.0.2', 'lessThan': '7.1', 'versionType': 'semver'}], 'programFiles': ['fs/smb/server/vfs_cache.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '7.1'}, {'status': 'unaffected', 'version': '0', 'lessThan': '7.1', 'versionType': 'semver'}, {'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': ['fs/smb/server/vfs_cache.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': '712cdf917e77a6444ce3836874829d770db20ee6', 'lessThan': 'fb978d72052704c6b06c6b0f129fcd60b77169f5', 'versionType': 'git'}, {'status': 'affected', 'version': 'c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d', 'lessThan': '93d4d46bf9d442a12ea87278049ec416962c627f', 'versionType': 'git'}, {'status': 'affected', 'version': '00ce8d6789dae72d042a4522264964c72891ca37', 'lessThan': '5a5ac2852cd326529d02f778bc1aa6184701f4d7', 'versionType': 'git'}, {'status': 'affected', 'version': '49110a8ce654bbe56bef7c5e44cce31f4b102b8a', 'lessThan': 'ed98719be41389d416953b8ef9f07a07dfea6b2b', 'versionType': 'git'}, {'status': 'affected', 'version': '49110a8ce654bbe56bef7c5e44cce31f4b102b8a', 'lessThan': '38637163501fd9e2f684b8cd275d0db5d79f37c6', 'versionType': 'git'}, {'status': 'affected', 'version': 'c908c853f304a4969b5aa10eba0b50350cc65b80', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.142', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.92', 'lessThan': '6.12.97', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.18.25', 'lessThan': '6.18.40', 'versionType': 'semver'}, {'status': 'affected', 'version': '7.0.2', 'lessThan': '7.1', 'versionType': 'semver'}], 'programFiles': ['fs/smb/server/vfs_cache.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '7.1'}, {'status': 'unaffected', 'version': '0', 'lessThan': '7.1', 'versionType': 'semver'}, {'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-rc2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/server/vfs_cache.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of fp->owner.name in durable handle owner check Two concurrent SMB2 durable reconnects (DH2C/DHnC) on the same persistent_id race the fp->owner.name compare-read in ksmbd_vfs_compare_durable_owner() against the kfree() in ksmbd_reopen_durable_fd()'s reopen-success path. fp->owner.name is a standalone kstrdup() buffer whose lifetime is independent of the fp refcount, and the two sites share no lock: the compare reads the buffer while the reopen frees it, so the strcmp() can dereference freed memory. Commit 7ce4fc40018d ("ksmbd: fix durable reconnect double-bind race in ksmbd_reopen_durable_fd") made the fp->conn claim atomic under global_ft.lock (closing the owner.name double-free and the ksmbd_file write-UAF), but the compare-read versus reopen-free pair was left unserialized. BUG: KASAN: slab-use-after-free in strcmp+0x2c/0x80 Read of size 1 by task kworker strcmp ksmbd_vfs_compare_durable_owner smb2_check_durable_oplock smb2_open Freed by task kworker: kfree ksmbd_reopen_durable_fd smb2_open Allocated by task kworker: kstrdup session_fd_check smb2_session_logoff The buggy address belongs to the cache kmalloc-8 Serialize both sides of the race with fp->f_lock. The global durable file-table lock still protects the durable reconnect claim, but fp->owner.name is per-open state and does not need to block unrelated durable table lookups or reconnects. The teardown is left at its existing location after the reopen-success point so that an __open_id() rollback still retains owner.name for a later legitimate reconnect to verify.
    Added Reference https://git.kernel.org/stable/c/38637163501fd9e2f684b8cd275d0db5d79f37c6
    Added Reference https://git.kernel.org/stable/c/5a5ac2852cd326529d02f778bc1aa6184701f4d7
    Added Reference https://git.kernel.org/stable/c/93d4d46bf9d442a12ea87278049ec416962c627f
    Added Reference https://git.kernel.org/stable/c/ed98719be41389d416953b8ef9f07a07dfea6b2b
    Added Reference https://git.kernel.org/stable/c/fb978d72052704c6b06c6b0f129fcd60b77169f5
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.