System hang via reversed CIFS client locks
Published May 20, 2024 · Updated Aug 5, 2026
Improper locking in the Linux CIFS client allows remote attackers controlling an SMB server to hang affected kernels. The cifs_sync_mid_result function acquires TCP_Server_Info.srv_lock while holding TCP_Server_Info.mid_lock, reversing another path's order and permitting deadlock. Reachability requires an active CIFS/SMB client connection to an attacker-controlled or intercepted server; the reported consequence is loss of availability, not data disclosure or modification.
Summary
What happened
Improper locking in the Linux CIFS client allows remote attackers controlling an SMB server to hang affected kernels. The cifs_sync_mid_result function acquires TCP_Server_Info.srv_lock while holding TCP_Server_Info.mid_lock, reversing another path's order and permitting deadlock. Reachability requires an active CIFS/SMB client connection to an attacker-controlled or intercepted server; the reported consequence is loss of availability, not data disclosure or modification.
The record
- CVE
- CVE-2024-35998
- Published
- May 20, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-667, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 20, 2024CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0b08c4c499200be67d54c439d56e5ea866869945
- Affected versionversion=6.1.28 <6.1.90
- Affected versionversion=6.2.15 <6.3
- Affected versionversion=6.3.2 <6.4
- Affected versionversion=6.4
- Affected versionversion=64d62ac6d6514cba1305bd08e271ec1843bdd612 <c7a4bca289e50bb4b2650f845c41bb3e453f4c66
- Affected versionversion=90c49fce1c43e1cc152695e20363ff5087897c09 <699f8958dece132709c0bff6a9700999a2a63b75
- Affected versionversion=90c49fce1c43e1cc152695e20363ff5087897c09 <8248224ab5b8ca7559b671917c224296a4d671fc
- Affected versionversion=90c49fce1c43e1cc152695e20363ff5087897c09 <8861fd5180476f45f9e8853db154600469a0284f
- Affected versionversion=c511954bf142fe1995aec3c739a9f1a76990283a
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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