# CVE-2026-72381: linux: In the Linux kernel, the following vulnerability has been resolved:  ksmbd: fix use-after-free of fp->owner.name in d...

CVE-2026-72381 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-72381, released August 15, 2026. It is not reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2026-72381
- Priority: Urgent
- CVSS: 9.8 (critical)
- EPSS: 0.0065
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 15, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  ksmbd: fix use-after-free of fp->owner.name in durable handle owner check  Two concurrent SMB2 durable reconnects (DH2C/DHnC) on the same persistent_id race the fp->owner.name compare-read in ksmbd_vfs_compare_durable_owner() against the kfree() in ksmbd_reopen_durable_fd()'s reopen-success path. fp->owner.name is a standalone kstrdup() buffer whose lifetime is independent of the fp refcount, and the two sites share no lock: the compare reads the buffer while the reopen frees it, so the strcmp() can dereference freed memory.  Commit 7ce4fc40018d ("ksmbd: fix durable reconnect double-bind race in ksmbd_reopen_durable_fd") made the fp->conn claim atomic under global_ft.lock (closing the owner.name double-free and the ksmbd_file write-UAF), but the compare-read versus reopen-free pair was left unserialized.    BUG: KASAN: slab-use-after-free in strcmp+0x2c/0x80   Read of size 1 by task kworker     strcmp     ksmbd_vfs_compare_durable_owner     smb2_check_durable_oplock     smb2_open   Freed by task kworker:     kfree     ksmbd_reopen_durable_fd     smb2_open   Allocated by task kworker:     kstrdup     session_fd_check     smb2_session_logoff   The buggy address belongs to the cache kmalloc-8  Serialize both sides of the race with fp->f_lock.  The global durable file-table lock still protects the durable reconnect claim, but fp->owner.name is per-open state and does not need to block unrelated durable table lookups or reconnects.  The teardown is left at its existing location after the reopen-success point so that an __open_id() rollback still retains owner.name for a later legitimate reconnect to verify.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 13.5 (trixie) | 6.12.100-1 | [DEBIAN-CVE-2026-72381](https://patchblox.com/security/data/fix/linux/debian-cve-2026-72381.md) | Aug 15, 2026 |
| Linux | linux Debian 14 | 7.1.5-1 | [DEBIAN-CVE-2026-72381](https://patchblox.com/security/data/fix/linux/debian-cve-2026-72381.md) | Aug 15, 2026 |

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Data as of 2026-11-09T19:38:12Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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