CVE-2026-72381: linux
Vulnerability summary
CVE-2026-72381 is a critical (CVSS 9.8) vulnerability in linux. EPSS estimates a 0.65% chance of exploitation in the next 30 days, higher than 50.3% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 6 · Related 6Timeline
- 15-08-2026PublishedVulnerability first disclosed.
- 17-08-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.65%
Chance of exploitation in the next 30 days
Percentile
50%
Versus all other CVEs
30-day change
+0.01 pp
From 0.64% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Ubuntu115 products
- linux< 7.0.0-34.34
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 7.0.0-1013.13
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian1 product
- linux< 6.12.100-1 | < 7.1.5-1
Linux1 product
- linux≥ 712cdf917e77a6444ce3836874829d770db20ee6, < fb978d72052704c6b06c6b0f129fcd60b77169f5 | ≥ c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d, < 93d4d46bf9d442a12ea87278049ec416962c627f | ≥ 00ce8d6789dae72d042a4522264964c72891ca37, < 5a5ac2852cd326529d02f778bc1aa6184701f4d7 | ≥ 49110a8ce654bbe56bef7c5e44cce31f4b102b8a, < ed98719be41389d416953b8ef9f07a07dfea6b2b | ≥ 49110a8ce654bbe56bef7c5e44cce31f4b102b8a, < 38637163501fd9e2f684b8cd275d0db5d79f37c6 | c908c853f304a4969b5aa10eba0b50350cc65b80 | ≥ 6.6.142, < 6.6.145 | ≥ 6.12.92, < 6.12.97 | ≥ 6.18.25, < 6.18.40 | ≥ 7.0.2, < 7.1 | 7.1
3 vendors · 117 products