Critical 9.8Published Dec 30, 2025

CVE-2023-54258cifs: fix potential oops in cifs_oplock_break

Updated under an hour ago (Oct 27, 2026, 1:00 AM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: cifs: fix potential oops in cifs_oplock_break With deferred close we can have closes that race with lease breaks, and so with the current checks for whether to send the lease response, oplock_response(), this can mean that an unmount (kill_sb) can occur just before we were checking if the tcon->ses is valid. See below: [Fri Aug 4 04:12:50 2023] RIP: 0010:cifs_oplock_break+0x1f7/0x5b0 [cifs] [Fri Aug 4 04:12:50 2023] Code: 7d a8 48 8b 7d c0 c0 e9 02 48 89 45 b8 41 89 cf e8 3e f5 ff ff 4c 89 f7 41 83 e7 01 e8 82 b3 03 f2 49 8b 45 50 48 85 c0 74 5e <48> 83 78 60 00 74 57 45 84 ff 75 52 48 8b 43 98 48 83 eb 68 48 39 [Fri Aug 4 04:12:50 2023] RSP: 0018:ffffb30607ddbdf8 EFLAGS: 00010206 [Fri Aug 4 04:12:50 2023] RAX: 632d223d32612022 RBX: ffff97136944b1e0 RCX: 0000000080100009 [Fri Aug 4 04:12:50 2023] RDX: 0000000000000001 RSI: 0000000080100009 RDI: ffff97136944b188 [Fri Aug 4 04:12:50 2023] RBP: ffffb30607ddbe58 R08: 0000000000000001 R09: ffffffffc08e0900 [Fri Aug 4 04:12:50 2023] R10: 0000000000000001 R11: 000000000000000f R12: ffff97136944b138 [Fri Aug 4 04:12:50 2023] R13: ffff97149147c000 R14: ffff97136944b188 R15: 0000000000000000 [Fri Aug 4 04:12:50 2023] FS: 0000000000000000(0000) GS:ffff9714f7c00000(0000) knlGS:0000000000000000 [Fri Aug 4 04:12:50 2023] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [Fri Aug 4 04:12:50 2023] CR2: 00007fd8de9c7590 CR3: 000000011228e000 CR4: 0000000000350ef0 [Fri Aug 4 04:12:50 2023] Call Trace: [Fri Aug 4 04:12:50 2023] <TASK> [Fri Aug 4 04:12:50 2023] process_one_work+0x225/0x3d0 [Fri Aug 4 04:12:50 2023] worker_thread+0x4d/0x3e0 [Fri Aug 4 04:12:50 2023] ? process_one_work+0x3d0/0x3d0 [Fri Aug 4 04:12:50 2023] kthread+0x12a/0x150 [Fri Aug 4 04:12:50 2023] ? set_kthread_struct+0x50/0x50 [Fri Aug 4 04:12:50 2023] ret_from_fork+0x22/0x30 [Fri Aug 4 04:12:50 2023] </TASK> To fix this change the ordering of the checks before sending the oplock_response to first check if the openFileList is empty.

CVSS: 9.8 CRITICAL (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Deferred
Record last updated: Oct 15, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 63fb45ddc491895c4b36664e0c2c3b548545ae93 before b99f490ea87ebcca3a429fd8837067feb56a4c7c; from 1bf709b9625001eefdd41048c5f4c7544ee33394 before 5ee28bcfbaacf289eb25c662a2862542ea6ce6a7; from 3b4c15171c3ce9120c81f5564b9367d8d0f4219c before 6b67a6d2e50634fe127e656147c81915955e9f5e; from da787d5b74983f7525d1eb4b9c0b4aff2821511a before e8f5f849ffce24490eb9449e98312b66c0dba76f; cff7fb969edaeff2bc80c8a8f7cf7b0c8df32da7; from 6.3.13 before 6.4	CNA record

References

References

https://git.kernel.org/stable/c/b99f490ea87ebcca3a429fd8837067feb56a4c7c
https://git.kernel.org/stable/c/5ee28bcfbaacf289eb25c662a2862542ea6ce6a7
https://git.kernel.org/stable/c/6b67a6d2e50634fe127e656147c81915955e9f5e
https://git.kernel.org/stable/c/e8f5f849ffce24490eb9449e98312b66c0dba76f

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.