Network denial of service via conntrack deadlock
Published Aug 22, 2026 · Updated Aug 25, 2026
Denial of service in affected Linux netfilter conntrack code allows remote attackers to hang kernel networking via crafted TCP or SCTP traffic. Invalid-packet logging occurs while ct->lock is held, and nfnetlink_log re-enters conntrack export code that tries to acquire the same lock. The deadlock requires conntrack invalid logging, NFLOG routing, and conntrack export; it can stall networking or cause a watchdog-triggered kernel panic.
Summary
What happened
Denial of service in affected Linux netfilter conntrack code allows remote attackers to hang kernel networking via crafted TCP or SCTP traffic. Invalid-packet logging occurs while ct->lock is held, and nfnetlink_log re-enters conntrack export code that tries to acquire the same lock. The deadlock requires conntrack invalid logging, NFLOG routing, and conntrack export; it can stall networking or cause a watchdog-triggered kernel panic.
The record
- CVE
- CVE-2026-74624
- Published
- Aug 22, 2026
- Updated
- Aug 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-833, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 22, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 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=6.1
- Affected versionversion=d9a6f0d0df1899ff9086a57abc600e414f4b8cdd <0424186d570aa4d1ad17f516afb86bd9eaa4f42e
- Affected versionversion=d9a6f0d0df1899ff9086a57abc600e414f4b8cdd <2d19b95c9723001f214f7a47d67b09f46238f200
- Affected versionversion=d9a6f0d0df1899ff9086a57abc600e414f4b8cdd <63853eb20bba4e00b7cd0b8cfc19337bbaaf5037
- Affected versionversion=d9a6f0d0df1899ff9086a57abc600e414f4b8cdd <9480fcf70a5aa9d320088a01c95df0e5e6391f4a
- Affected versionversion=d9a6f0d0df1899ff9086a57abc600e414f4b8cdd <c0224327b7cbed9d3198e8dbec847281053dcd06
- Affected versionversion=d9a6f0d0df1899ff9086a57abc600e414f4b8cdd <ca97360eba4b3dc67f1804625542f4ccc774242a
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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