Kernel memory corruption via vsock refcount decrement
Published Aug 22, 2025 · Updated Aug 5, 2026
Use-after-free in the Linux kernel vsock subsystem allows local users to corrupt kernel memory through a bound socket. The __vsock_bind_connectible() path permits VMADDR_PORT_ANY; an accepted socket is absent from the unbound list, so rebinding decrements its reference count again. Exploitation requires local access and a usable vsock transport; the resulting memory corruption can crash or compromise the kernel.
Summary
What happened
Use-after-free in the Linux kernel vsock subsystem allows local users to corrupt kernel memory through a bound socket. The __vsock_bind_connectible() path permits VMADDR_PORT_ANY; an accepted socket is absent from the unbound list, so rebinding decrements its reference count again. Exploitation requires local access and a usable vsock transport; the resulting memory corruption can crash or compromise the kernel.
The record
- CVE
- CVE-2025-38618
- Published
- Aug 22, 2025
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 22, 2025CVE 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=3.9
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <32950b1907919be86a7a2697d6f93d57068b3865
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <44bd006d5c93f6a8f28b106cbae2428c5d0275b7
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <8f01093646b49f6330bb2d36761983fd829472b1
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <aba0c94f61ec05315fa7815d21aefa4c87f6a9f4
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <c04a2c1ca25b9b23104124d3b2d349d934e302de
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <cf86704798c1b9c46fa59dfc2d662f57d1394d79
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <d1a5b1964cef42727668ac0d8532dae4f8c19386
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <d73960f0cf03ef1dc9e96ec7a20e538accc26d87
- Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <f138be5d7f301fddad4e65ec66dfc3ceebf79be3
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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