Remote kernel corruption via SMC socket lifetime race
Published Aug 15, 2026 · Updated Aug 15, 2026
Use-after-free in Linux net/smc allows remote attackers to corrupt kernel memory through an SMC peer connection during link-group termination. __smc_lgr_terminate() releases conns_lock before holding the embedded socket, so concurrent connection removal can free it before sock_hold() increments its reference. An unauthenticated SMC peer must overlap termination with teardown; successful triggering permits memory corruption and can crash the kernel.
Summary
What happened
Use-after-free in Linux net/smc allows remote attackers to corrupt kernel memory through an SMC peer connection during link-group termination. __smc_lgr_terminate() releases conns_lock before holding the embedded socket, so concurrent connection removal can free it before sock_hold() increments its reference. An unauthenticated SMC peer must overlap termination with teardown; successful triggering permits memory corruption and can crash the kernel.
The record
- CVE
- CVE-2026-74493
- Published
- Aug 15, 2026
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-825, T1499
- Attack vector
- network
- Privileges
- unauthenticated
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
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Is a vulnerable build present?
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- Affected versionversion=5.5
- Affected versionversion=69318b5215f2dc32c345a3d65b98b4b1bf29c007 <281c103a8eaed59001ce952f231df1b07674215a
- Affected versionversion=69318b5215f2dc32c345a3d65b98b4b1bf29c007 <5a42f162b857019a4c10ff687dc3bcdf51831865
- Affected versionversion=69318b5215f2dc32c345a3d65b98b4b1bf29c007 <f0541a775d04c88e90ba448e35ce0d743512822a
- Affected versionversion=69318b5215f2dc32c345a3d65b98b4b1bf29c007 <f621d6ebeebb6374342571e4ddf45fdbc420f6cd
- Affected versionversion=69318b5215f2dc32c345a3d65b98b4b1bf29c007 <f807a63d0d95680c34f677700da9148a07d7c78f
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
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Technologies
Your stack
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Your stack
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