Authenticated denial of service via DACL underflow
Published Aug 15, 2026 · Updated Aug 15, 2026
Denial of service in Linux kernel ksmbd allows remote authenticated users to exhaust memory via an undersized DACL in SMB2_SET_INFO. parse_dacl() subtracts the unsigned ACL-header size from a smaller attacker-controlled 16-bit DACL size, underflows to a large size_t, and accepts an excessive ACE count. The path requires valid SMB credentials and an active ksmbd server; the bounded impact is excessive temporary allocation and service interruption.
Summary
What happened
Denial of service in Linux kernel ksmbd allows remote authenticated users to exhaust memory via an undersized DACL in SMB2_SET_INFO. parse_dacl() subtracts the unsigned ACL-header size from a smaller attacker-controlled 16-bit DACL size, underflows to a large size_t, and accepts an excessive ACE count. The path requires valid SMB credentials and an active ksmbd server; the bounded impact is excessive temporary allocation and service interruption.
The record
- CVE
- CVE-2026-72382
- Published
- Aug 15, 2026
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-131, T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 15, 2026CVE publishedPublication date reported by the CVE source.
- Aug 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.15
- Affected versionversion=e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <15a9e9b8f7f5d7f380ae54c6f5bcbc0bdcb0f3cd
- Affected versionversion=e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <16fb65ec15fe7c90f50a2115854bfd9a032d4023
- Affected versionversion=e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <282847c0cf22f2e961155ac8e42f6eeab7e16049
- Affected versionversion=e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <60908f7ebcd9b6cde74ad5711fab0f49c7970949
- Affected versionversion=e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 <d020e7f27bf65eecd3805404702f716b2b6d9e73
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo