Kernel memory corruption via XFRM cache double-release
Published Aug 5, 2026 · Updated Aug 5, 2026
Use-after-free in the Linux kernel 4.14 through 7.1.5 allows local users to corrupt kernel memory via a UDP socket race. xfrm_user_policy() non-atomically clears and releases sk_dst_cache while udp_sendmsg can atomically exchange the same pointer, so both threads release one reference. Unprivileged access suffices when user and network namespaces are available, and successful reuse can disclose or modify kernel memory, hijack control flow, or panic the host.
Summary
What happened
Use-after-free in the Linux kernel 4.14 through 7.1.5 allows local users to corrupt kernel memory via a UDP socket race. xfrm_user_policy() non-atomically clears and releases sk_dst_cache while udp_sendmsg can atomically exchange the same pointer, so both threads release one reference. Unprivileged access suffices when user and network namespaces are available, and successful reuse can disclose or modify kernel memory, hijack control flow, or panic the host.
The record
- CVE
- CVE-2026-64581
- Published
- Aug 5, 2026
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 5, 2026CVE 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=2b06cdf3e688b98fcc9945873b5d42792bd4eee0 <96b678d08268b5f5c6fc99d4289d9b7e334fc683
- Affected versionversion=2b06cdf3e688b98fcc9945873b5d42792bd4eee0 <c283e9ada7fcb7dd4b10592623086b2e6d2f9925
- Affected versionversion=3.16.52 <3.17
- Affected versionversion=3.18.101 <3.19
- Affected versionversion=4.14
- Affected versionversion=4.1.52 <4.2
- Affected versionversion=4.4.123 <4.5
- Affected versionversion=4.4.163 <4.5
- Affected versionversion=4.9.89 <4.10
- Affected versionversion=5eef9b51114fcc65651d671add52f267f91b9451
- Affected versionversion=72f157be2f81910ae759bfe2e5c2256fc4625645
- Affected versionversion=9e9fe58a92a46c6d154d2901735bf230d91b8507
- Affected versionversion=adc1ec6cdc20d430aa01b86497220709b9149466
- Affected versionversion=b54033eb1cfd77aba471269ddd804ed8d3e35dea
- Affected versionversion=c9e82cb34c3c2ee895af01bc899c6ed0bc6eb04a
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Technologies
Your stack
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