Kernel crash via premature cross-SYN socket shutdown
Published May 30, 2024 · Updated May 12, 2026
Divide-by-zero in the Linux kernel before 6.9 allows local users to crash the kernel through a cross-SYN TCP socket shutdown. tcp_shutdown moves a TCP_SYN_RECV socket to TCP_FIN_WAIT1 before tcp_init_transfer initializes its receive-buffer state, leaving tcp_rcv_space_adjust to divide by zero. The caller needs low-privilege local socket access and control of the unusual cross-SYN state sequence; the documented consequence is system interruption, not data access or modification.
Summary
What happened
Divide-by-zero in the Linux kernel before 6.9 allows local users to crash the kernel through a cross-SYN TCP socket shutdown. tcp_shutdown moves a TCP_SYN_RECV socket to TCP_FIN_WAIT1 before tcp_init_transfer initializes its receive-buffer state, leaving tcp_rcv_space_adjust to divide by zero. The caller needs low-privilege local socket access and control of the unusual cross-SYN state sequence; the documented consequence is system interruption, not data access or modification.
The record
- CVE
- CVE-2024-36905
- Published
- May 30, 2024
- Updated
- May 12, 2026
- Vendor
- Siemens
- Product
- SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
- Classifications
- CWE-369, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 30, 2024CVE publishedPublication date reported by the CVE source.
- May 12, 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?
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- Affected versionversion=V3.1.0 <V3.1.5
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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