Authenticated use-after-free via oplock break race
Published Sep 11, 2026 · Updated Sep 11, 2026
Use-after-free in Linux ksmbd allows remote authenticated users to dereference stale connection memory during an oplock break. smb2_oplock_break_noti() reads opinfo->conn without ci->m_lock, sleeps during allocation, and then increments and queues work against a connection that teardown can free. The attacker must hold a durable batch oplock and race its disconnect with a break from another connection; the published fix establishes stale kernel-memory access but does not specify a further consequence.
Summary
What happened
Use-after-free in Linux ksmbd allows remote authenticated users to dereference stale connection memory during an oplock break. smb2_oplock_break_noti() reads opinfo->conn without ci->m_lock, sleeps during allocation, and then increments and queues work against a connection that teardown can free. The attacker must hold a durable batch oplock and race its disconnect with a break from another connection; the published fix establishes stale kernel-memory access but does not specify a further consequence.
The record
- CVE
- CVE-2026-80926
- Published
- Sep 11, 2026
- Updated
- Sep 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 11, 2026CVE publishedPublication date reported by the CVE source.
- Sep 11, 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=1ff58dcfcab434ebb51649da33774fbb8e1f7b67
- Affected versionversion=6.12.94 <6.13
- Affected versionversion=6.18.36 <6.18.51
- Affected versionversion=6.6.143 <6.7
- Affected versionversion=7.0.13 <7.1
- Affected versionversion=7.1
- Affected versionversion=75e33deda658c1ab3a9336cbdb1436536f9b3660
- Affected versionversion=945a86b21b40fb17183f5b27461baa6f03e2467f
- Affected versionversion=b003086d76968298f22e7cf62239833b5a3a06b1 <0e753899627b5e28a9fea8bca98262a6f65a2452
- Affected versionversion=b003086d76968298f22e7cf62239833b5a3a06b1 <8cc98db4fc590e6c7d9db6529320982ee16c5d1d
- Affected versionversion=e735dbd489e3ea02be78dba991056fe1138be51e <c8279ae8df68cce9cd3b785e85f7a86c80a46e78
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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
No sourced classifications are available.
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