CVE-2026-97558 (GCVE-0-2026-97558)
Vulnerability from cvelistv5 – Published: 2026-09-25 10:21 – Updated: 2026-10-30 12:37
VLAI
EPSS
VEX
Title
smb: client: fix cifsFileInfo reference leak in deferred close
Summary
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.
Severity
No CVSS data available.
Assigner
References
7 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
c3f207ab29f793b8c942ce8067ed123f18d5b81b , < 645a7359c1f740152464edf84f1030e0cad42c9d
(git)
Affected: c3f207ab29f793b8c942ce8067ed123f18d5b81b , < 46d98be6c34a52182ea3c2f849a3ea0e9419eaf2 (git) Affected: c3f207ab29f793b8c942ce8067ed123f18d5b81b , < 525c225e23d61694091f2806de553a69362a78ff (git) Affected: c3f207ab29f793b8c942ce8067ed123f18d5b81b , < bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6 (git) Affected: c3f207ab29f793b8c942ce8067ed123f18d5b81b , < a6767712902beb0f53238be485971c9a83ea1079 (git) Affected: c3f207ab29f793b8c942ce8067ed123f18d5b81b , < ea93759d6c2789924f4e557aed5be532207715ea (git) Affected: c3f207ab29f793b8c942ce8067ed123f18d5b81b , < 5520e89a5a4f834bced64cf2ac927001cc513a40 (git) |
guessed | |
| Linux | Linux |
Affected:
5.13
Unaffected: 0 , < 5.13 (semver) Unaffected: 5.15.224 , ≤ 5.15.* (semver) Unaffected: 6.1.191 , ≤ 6.1.* (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.54 , ≤ 6.18.* (semver) Unaffected: 7.2.7 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix) |
guessed |
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],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
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"version": "5.13"
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{
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"status": "unaffected",
"version": "0",
"versionType": "semver"
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{
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"status": "unaffected",
"version": "5.15.224",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.191",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.54",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.2.*",
"status": "unaffected",
"version": "7.2.7",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
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"versionStartIncluding": "5.13",
"vulnerable": true
},
{
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},
{
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},
{
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"versionStartIncluding": "5.13",
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},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.54",
"versionStartIncluding": "5.13",
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},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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}
],
"negate": false,
"operator": "OR"
}
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}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix cifsFileInfo reference leak in deferred close\n\nWhen cifs_close() defers a close, it hands the cifsFileInfo reference\nof the closing struct file to the queued work. Each execution of\nsmb2_deferred_work_close() drops one such reference.\n\ndeferred_close_scheduled can be false while the work is pending: the\nworkqueue clears PENDING when the callback starts to run, before the\ncallback clears the flag under deferred_lock. A close in that\ninterval requeues the running work, and the callback then clears the\nflag, leaving the requeued work pending with the flag down. A later\ncifs_open() can reuse the handle and its cifs_close() reaches the\nsame branch: queue_delayed_work() fails because the work is still\npending, but cifs_close() returns without dropping the closing file\u0027s\nreference. The cifsFileInfo count stays pinned and its tlink, dentry\nand server handle are leaked.\n\nCheck the return value and hand off the reference only when work was\nactually queued. Otherwise, use the shared _cifsFileInfo_put(), like\nthe mod_delayed_work() branch above: the pending execution already\nowns its reference.\n\nThis issue was found by an in-house static analysis tool."
}
],
"providerMetadata": {
"dateUpdated": "2026-10-30T12:37:23.189Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/645a7359c1f740152464edf84f1030e0cad42c9d"
},
{
"url": "https://git.kernel.org/stable/c/46d98be6c34a52182ea3c2f849a3ea0e9419eaf2"
},
{
"url": "https://git.kernel.org/stable/c/525c225e23d61694091f2806de553a69362a78ff"
},
{
"url": "https://git.kernel.org/stable/c/bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6"
},
{
"url": "https://git.kernel.org/stable/c/a6767712902beb0f53238be485971c9a83ea1079"
},
{
"url": "https://git.kernel.org/stable/c/ea93759d6c2789924f4e557aed5be532207715ea"
},
{
"url": "https://git.kernel.org/stable/c/5520e89a5a4f834bced64cf2ac927001cc513a40"
}
],
"title": "smb: client: fix cifsFileInfo reference leak in deferred close",
"x_generator": {
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}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-97558",
"datePublished": "2026-09-25T10:21:48.277Z",
"dateReserved": "2026-09-24T16:01:01.155Z",
"dateUpdated": "2026-10-30T12:37:23.189Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-97558",
"date": "2026-11-14",
"epss": "0.00228",
"percentile": "0.13712"
},
"microsoft_vex": {
"current_release_date": "2026-11-07T01:48:32.000Z",
"cve": "CVE-2026-97558",
"id": "msrc_CVE-2026-97558",
"initial_release_date": "2026-09-27T23:33:52.000Z",
"product_status:fixed": "1",
"product_status:known_affected": "2",
"product_status:under_investigation": "1",
"source": "Microsoft CSAF VEX",
"status": "final",
"title": "smb: client: fix cifsFileInfo reference leak in deferred close",
"url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-97558.json",
"version": "5"
},
"nvd": {
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{
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"product": "Linux",
"programFiles": [
"fs/smb/client/file.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
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"versionType": "git"
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"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
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"version": "5.13"
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{
"lessThan": "5.13",
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"version": "0",
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{
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},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
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},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver"
},
{
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"status": "unaffected",
"version": "6.18.54",
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},
{
"lessThanOrEqual": "7.2.*",
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"version": "7.2.7",
"versionType": "semver"
},
{
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"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix cifsFileInfo reference leak in deferred close\n\nWhen cifs_close() defers a close, it hands the cifsFileInfo reference\nof the closing struct file to the queued work. Each execution of\nsmb2_deferred_work_close() drops one such reference.\n\ndeferred_close_scheduled can be false while the work is pending: the\nworkqueue clears PENDING when the callback starts to run, before the\ncallback clears the flag under deferred_lock. A close in that\ninterval requeues the running work, and the callback then clears the\nflag, leaving the requeued work pending with the flag down. A later\ncifs_open() can reuse the handle and its cifs_close() reaches the\nsame branch: queue_delayed_work() fails because the work is still\npending, but cifs_close() returns without dropping the closing file\u0027s\nreference. The cifsFileInfo count stays pinned and its tlink, dentry\nand server handle are leaked.\n\nCheck the return value and hand off the reference only when work was\nactually queued. Otherwise, use the shared _cifsFileInfo_put(), like\nthe mod_delayed_work() branch above: the pending execution already\nowns its reference.\n\nThis issue was found by an in-house static analysis tool."
}
],
"id": "CVE-2026-97558",
"lastModified": "2026-10-30T13:21:07.977",
"metrics": {},
"published": "2026-09-25T11:17:06.320",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/46d98be6c34a52182ea3c2f849a3ea0e9419eaf2"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/525c225e23d61694091f2806de553a69362a78ff"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/5520e89a5a4f834bced64cf2ac927001cc513a40"
},
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"url": "https://git.kernel.org/stable/c/a6767712902beb0f53238be485971c9a83ea1079"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6"
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}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Received"
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-11-06T02:24:26+00:00",
"cve": "CVE-2026-97558",
"id": "CVE-2026-97558",
"initial_release_date": "2026-09-25T00:00:00+00:00",
"product_status:known_affected": "112",
"product_status:known_not_affected": "91",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: smb: client: fix cifsFileInfo reference leak in deferred close",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97558.json",
"version": "3"
}
}
}
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|---|
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