Remote kernel compromise via asynchronous AEAD use-after-free
Published Jul 25, 2026 · Updated Jul 25, 2026
Use-after-free in the Kerberos crypto helpers in Linux Kernel allows remote attackers to compromise the kernel via network packets. The encrypt and decrypt helpers set no completion callback, treat -EINPROGRESS as terminal, and free a request buffer that the asynchronous AEAD worker later dereferences. Reachability requires a network-driven RxRPC/RxGK, AFS, or Ceph path and an asynchronous AEAD provider bound to the Kerberos enctype; exploitation allows kernel-memory disclosure, corruption, or a panic.
Summary
What happened
Use-after-free in the Kerberos crypto helpers in Linux Kernel allows remote attackers to compromise the kernel via network packets. The encrypt and decrypt helpers set no completion callback, treat -EINPROGRESS as terminal, and free a request buffer that the asynchronous AEAD worker later dereferences. Reachability requires a network-driven RxRPC/RxGK, AFS, or Ceph path and an asynchronous AEAD provider bound to the Kerberos enctype; exploitation allows kernel-memory disclosure, corruption, or a panic.
The record
- CVE
- CVE-2026-64439
- Published
- Jul 25, 2026
- Updated
- Jul 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1210
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 25, 2026CVE publishedPublication date reported by the CVE source.
- Jul 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?
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- Affected versionversion=00244da40f7821b242c4612428d4192230dba27f <2b7bd6dccff14b8b632c5244f1fd506918077221
- Affected versionversion=00244da40f7821b242c4612428d4192230dba27f <6c9dddeb582fde005360f4fe02c760d45ca05fb5
- Affected versionversion=00244da40f7821b242c4612428d4192230dba27f <ef6feb77e2d91761427c5b773edc9c97e1b706ad
- Affected versionversion=6.15
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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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