CVE-2026-97558smb: client: fix cifsFileInfo reference leak in deferred close
- —Not scoredno CVSS score yet
- 0.23%Exploitation in 30 daysEPSS · top 86% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix cifsFileInfo reference leak in deferred close When cifs_close() defers a close, it hands the cifsFileInfo reference of the closing struct file to the queued work. Each execution of smb2_deferred_work_close() drops one such reference. deferred_close_scheduled can be false while the work is pending: the workqueue clears PENDING when the callback starts to run, before the callback clears the flag under deferred_lock. A close in that interval requeues the running work, and the callback then clears the flag, leaving the requeued work pending with the flag down. A later cifs_open() can reuse the handle and its cifs_close() reaches the same branch: queue_delayed_work() fails because the work is still pending, but cifs_close() returns without dropping the closing file's reference. The cifsFileInfo count stays pinned and its tlink, dentry and server handle are leaked. Check the return value and hand off the reference only when work was actually queued. Otherwise, use the shared _cifsFileInfo_put(), like the mod_delayed_work() branch above: the pending execution already owns its reference. This issue was found by an in-house static analysis tool.
Timeline
ID reserved
By Linux
- 1 day later
· 1 day later
Published
- 35 days later
· 35 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.23% · top 86% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < 645a7359c1f740152464edf84f1030e0cad42c9d
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < 46d98be6c34a52182ea3c2f849a3ea0e9419eaf2
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < 525c225e23d61694091f2806de553a69362a78ff
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < a6767712902beb0f53238be485971c9a83ea1079
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < ea93759d6c2789924f4e557aed5be532207715ea
- affected c3f207ab29f793b8c942ce8067ed123f18d5b81b – < 5520e89a5a4f834bced64cf2ac927001cc513a40
- affected 5.13
- unaffected < 5.13
- unaffected 5.15.224 – ≤ 5.15.*
- unaffected 6.1.191 – ≤ 6.1.*
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.113 – ≤ 6.12.*
- unaffected 6.18.54 – ≤ 6.18.*
- unaffected 7.2.7 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References7
- https://git.kernel.org/stable/c/645a7359c1f740152464edf84f1030e0cad42c9d (opens in a new tab)
- https://git.kernel.org/stable/c/46d98be6c34a52182ea3c2f849a3ea0e9419eaf2 (opens in a new tab)
- https://git.kernel.org/stable/c/525c225e23d61694091f2806de553a69362a78ff (opens in a new tab)
- https://git.kernel.org/stable/c/bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6 (opens in a new tab)
- https://git.kernel.org/stable/c/a6767712902beb0f53238be485971c9a83ea1079 (opens in a new tab)
- https://git.kernel.org/stable/c/ea93759d6c2789924f4e557aed5be532207715ea (opens in a new tab)
- https://git.kernel.org/stable/c/5520e89a5a4f834bced64cf2ac927001cc513a40 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-86866 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-97558)Record last updated .