Local privilege escalation via AF_IUCV teardown race
Published Aug 17, 2024 · Updated Aug 5, 2026
Use-after-free in the Linux kernel AF_IUCV subsystem allows local users to crash the host or escalate privileges through a socket race. iucv_sock_close() tests iucv->path without an atomic compare-and-swap, so a concurrent iucv_callback_connrej() can sever and free the path before the close path dereferences it. An unprivileged user on an s390 system with AF_IUCV support can race socket closes; successful reuse can expose or corrupt kernel memory, while the observed failure is a kernel panic.
Summary
What happened
Use-after-free in the Linux kernel AF_IUCV subsystem allows local users to crash the host or escalate privileges through a socket race. iucv_sock_close() tests iucv->path without an atomic compare-and-swap, so a concurrent iucv_callback_connrej() can sever and free the path before the close path dereferences it. An unprivileged user on an s390 system with AF_IUCV support can race socket closes; successful reuse can expose or corrupt kernel memory, while the observed failure is a kernel panic.
The record
- CVE
- CVE-2024-42271
- Published
- Aug 17, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 17, 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=3.4
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <01437282fd3904810603f3dc98d2cac6b8b6fc84
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <37652fbef9809411cea55ea5fa1a170e299efcd0
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <69620522c48ce8215e5eb55ffbab8cafee8f407d
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <84f40b46787ecb67c7ad08a5bb1376141fa10c01
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <8b424c9e44111c5a76f41c6b741f8d4c4179d876
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <ac758e1f663fe9bc64f6b47212a2aa18697524f5
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <c65f72eec60a34ace031426e04e9aff8e5f04895
- Affected versionversion=7d316b9453523498246e9e19a659c423d4c5081e <f558120cd709682b739207b48cf7479fd9568431
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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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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