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
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- 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.
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-2026-72381.
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.
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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