CVE-2026-72382
ksmbd: reject undersized DACLs before parsing ACEs
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: reject undersized DACLs before parsing ACEs parse_dacl() limits the attacker-controlled ACE count by comparing it with the number of minimal ACEs that fit in the DACL size. The DACL size field is 16 bits, but the expression subtracts sizeof(struct smb_acl). Because sizeof() is unsigned, a DACL size smaller than the ACL header underflows to a large size_t. A malicious client can reach this with: SMB2_SET_INFO (InfoType=SMB2_O_INFO_SECURITY) -> smb2_set_info_sec() -> set_info_sec() -> parse_sec_desc() -> parse_dacl() -> init_acl_state(..., 0xffff) -> init_acl_state(..., 0xffff) -> kmalloc_objs(..., 0xffff) Thus a malformed security descriptor can make num_aces pass the guard and drive large temporary ACL state and pointer-array allocations. Reject DACLs smaller than struct smb_acl before doing the subtraction, so the ACE count check cannot be bypassed by the underflow.
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 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel.
- Apply relevant security patches.
- Reboot the system after updates.
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-2026-72382.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-72382 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-2026-72382
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-2026-72382 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-72382 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: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': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '16fb65ec15fe7c90f50a2115854bfd9a032d4023', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '282847c0cf22f2e961155ac8e42f6eeab7e16049', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': 'd020e7f27bf65eecd3805404702f716b2b6d9e73', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '15a9e9b8f7f5d7f380ae54c6f5bcbc0bdcb0f3cd', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '60908f7ebcd9b6cde74ad5711fab0f49c7970949', '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': '6.6.145', '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/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': '16fb65ec15fe7c90f50a2115854bfd9a032d4023', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '282847c0cf22f2e961155ac8e42f6eeab7e16049', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': 'd020e7f27bf65eecd3805404702f716b2b6d9e73', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '15a9e9b8f7f5d7f380ae54c6f5bcbc0bdcb0f3cd', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '60908f7ebcd9b6cde74ad5711fab0f49c7970949', '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': '6.6.145', '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/smbacl.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': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '16fb65ec15fe7c90f50a2115854bfd9a032d4023', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '282847c0cf22f2e961155ac8e42f6eeab7e16049', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': 'd020e7f27bf65eecd3805404702f716b2b6d9e73', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '15a9e9b8f7f5d7f380ae54c6f5bcbc0bdcb0f3cd', 'versionType': 'git'}, {'status': 'affected', 'version': 'e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9', 'lessThan': '60908f7ebcd9b6cde74ad5711fab0f49c7970949', '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': '6.6.145', '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/smbacl.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: ksmbd: reject undersized DACLs before parsing ACEs parse_dacl() limits the attacker-controlled ACE count by comparing it with the number of minimal ACEs that fit in the DACL size. The DACL size field is 16 bits, but the expression subtracts sizeof(struct smb_acl). Because sizeof() is unsigned, a DACL size smaller than the ACL header underflows to a large size_t. A malicious client can reach this with: SMB2_SET_INFO (InfoType=SMB2_O_INFO_SECURITY) -> smb2_set_info_sec() -> set_info_sec() -> parse_sec_desc() -> parse_dacl() -> init_acl_state(..., 0xffff) -> init_acl_state(..., 0xffff) -> kmalloc_objs(..., 0xffff) Thus a malformed security descriptor can make num_aces pass the guard and drive large temporary ACL state and pointer-array allocations. Reject DACLs smaller than struct smb_acl before doing the subtraction, so the ACE count check cannot be bypassed by the underflow. Added Reference https://git.kernel.org/stable/c/15a9e9b8f7f5d7f380ae54c6f5bcbc0bdcb0f3cd Added Reference https://git.kernel.org/stable/c/16fb65ec15fe7c90f50a2115854bfd9a032d4023 Added Reference https://git.kernel.org/stable/c/282847c0cf22f2e961155ac8e42f6eeab7e16049 Added Reference https://git.kernel.org/stable/c/60908f7ebcd9b6cde74ad5711fab0f49c7970949 Added Reference https://git.kernel.org/stable/c/d020e7f27bf65eecd3805404702f716b2b6d9e73