ksmbd: fix null pointer dereference in compare_guid_key()
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in compare_guid_key() session_fd_check() walks the per-inode m_op_list during durable-handle session teardown and sets op->conn = NULL for every opinfo whose conn matched the closing session's connection. The matching opinfo, however, stays linked in its per-ClientGuid lease_table_list entry's lb->lease_list because destroy_lease_table() only runs on full TCP-connection teardown, not on SESSION_LOGOFF. If the same TCP connection then negotiates a fresh session with the same ClientGuid (ClientGuid is bound to NEGOTIATE, not the session, and is unchanged across LOGOFF + SETUP) and issues a SMB2 CREATE with a lease context on a different inode, find_same_lease_key() walks lb->lease_list, reaches the stale opinfo, and calls compare_guid_key(), which unconditionally dereferences opinfo->conn->ClientGUID. The conn pointer is NULL and the kernel panics. Reproducer requires only a successful SMB2 SESSION_SETUP and a share configured with 'durable handles = yes'. KASAN report on mainline 70390501d194: general protection fault, probably for non-canonical address 0xdffffc0000000069: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000348-0x000000000000034f] Workqueue: ksmbd-io handle_ksmbd_work RIP: 0010:bcmp+0x5b/0x230 Call Trace: compare_guid_key+0x4b/0xd0 find_same_lease_key+0x324/0x690 smb2_open+0x6aea/0x8e60 handle_ksmbd_work+0x796/0xee0 ... Faulting address 0x
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 6.12.92, 6.18.34, 6.6.142, 7.0.11
- CVEs
- CVE-2026-64141
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 7 Nov 2026, 07:41 UTC · Revision 1
Source evidence
ksmbd: fix null pointer dereference in compare_guid_key()
core-osv · Original sourcePublished 19 Jul 2026, 15:40 UTC
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in compare_guid_key() session_fd_check() walks the per-inode m_op_list during durable-handle session teardown and sets op->conn = NULL for every opinfo whose conn matched the closing session's connection. The matching opinfo, however, stays linked in its per-ClientGuid lease_table_list entry's lb->lease_list because destroy_lease_table() only runs on full TCP-connection teardown, not on SESSION_LOGOFF. If the same TCP connection then negotiates a fresh session with the same ClientGuid (ClientGuid is bound to NEGOTIATE, not the session, and is unchanged across LOGOFF + SETUP) and issues a SMB2 CREATE with a lease context on a different inode, find_same_lease_key() walks lb->lease_list, reaches the stale opinfo, and calls compare_guid_key(), which unconditionally dereferences opinfo->conn->ClientGUID. The conn pointer is NULL and the kernel panics. Reproducer requires only a successful SMB2 SESSION_SETUP and a share configured with 'durable handles = yes'. KASAN report on mainline 70390501d194: general protection fault, probably for non-canonical address 0xdffffc0000000069: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000348-0x000000000000034f] Workqueue: ksmbd-io handle_ksmbd_work RIP: 0010:bcmp+0x5b/0x230 Call Trace: compare_guid_key+0x4b/0xd0 find_same_lease_key+0x324/0x690 smb2_open+0x6aea/0x8e60 handle_ksmbd_work+0x796/0xee0 ... Faulting address 0x
osv:CVE-2026-64141
Kernel
Fixed versions: 6.6.142, 6.12.92, 6.18.34, 7.0.11
Complete source record
{
"id": "e99e9080dbcd95f52f4a4a44210ab257c1c9e9dc5dd2fd35b260bf6ab71608c6",
"url": "https://osv.dev/vulnerability/CVE-2026-64141",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "ksmbd: fix null pointer dereference in compare_guid_key()",
"summary": "In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in compare_guid_key() session_fd_check() walks the per-inode m_op_list during durable-handle session teardown and sets op->conn = NULL for every opinfo whose conn matched the closing session's connection. The matching opinfo, however, stays linked in its per-ClientGuid lease_table_list entry's lb->lease_list because destroy_lease_table() only runs on full TCP-connection teardown, not on SESSION_LOGOFF. If the same TCP connection then negotiates a fresh session with the same ClientGuid (ClientGuid is bound to NEGOTIATE, not the session, and is unchanged across LOGOFF + SETUP) and issues a SMB2 CREATE with a lease context on a different inode, find_same_lease_key() walks lb->lease_list, reaches the stale opinfo, and calls compare_guid_key(), which unconditionally dereferences opinfo->conn->ClientGUID. The conn pointer is NULL and the kernel panics. Reproducer requires only a successful SMB2 SESSION_SETUP and a share configured with 'durable handles = yes'. KASAN report on mainline 70390501d194: general protection fault, probably for non-canonical address 0xdffffc0000000069: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000348-0x000000000000034f] Workqueue: ksmbd-io handle_ksmbd_work RIP: 0010:bcmp+0x5b/0x230 Call Trace: compare_guid_key+0x4b/0xd0 find_same_lease_key+0x324/0x690 smb2_open+0x6aea/0x8e60 handle_ksmbd_work+0x796/0xee0 ... Faulting address 0x",
"evidence": "osv:CVE-2026-64141",
"products": [
{
"name": {
"value": "Kernel",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "6.6.142",
"evidence": "/affected/1/ranges"
},
{
"value": "6.12.92",
"evidence": "/affected/1/ranges"
},
{
"value": "6.18.34",
"evidence": "/affected/1/ranges"
},
{
"value": "7.0.11",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
}
],
"severity": "high",
"structured": {
"id": "CVE-2026-64141",
"aliases": [
"CVE-2026-64141"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "8df4bcdb0a4232192b2445256c39b787d58ef14d"
},
{
"fixed": "e43cb36d4d7827710cfcd48e95e29a507f0d87be"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "c8efcc786146a951091588e5fa7e3c754850cb3c"
},
{
"fixed": "0836081b394ca074d1b910f2b990ff7b4b4404c7"
},
{
"fixed": "cd5c1b75d2f454f625d7dc55bd3ae21d0855f6ad"
},
{
"fixed": "af86896ca3239e25a6bd7d352213371265073d38"
},
{
"fixed": "4b83cbc4c15f09b000cc06f033f64b0824b6dc87"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "6.6.32"
},
{
"fixed": "6.6.142"
}
]
}
],
"versions": [
"v6.6.141",
"v6.6.140",
"v6.6.139",
"v6.6.138",
"v6.6.137",
"v6.6.136",
"v6.6.135",
"v6.6.134",
"v6.6.133",
"v6.6.132",
"v6.6.131",
"v6.6.130",
"v6.6.129",
"v6.6.128",
"v6.6.127",
"v6.6.126",
"v6.6.125",
"v6.6.124",
"v6.6.123",
"v6.6.122",
"v6.6.121",
"v6.6.120",
"v6.6.119",
"v6.6.118",
"v6.6.117",
"v6.6.116",
"v6.6.115",
"v6.6.114",
"v6.6.113",
"v6.6.112",
"v6.6.111",
"v6.6.110",
"v6.6.109",
"v6.6.108",
"v6.6.107",
"v6.6.106",
"v6.6.105",
"v6.6.104",
"v6.6.103",
"v6.6.102",
"v6.6.101",
"v6.6.100",
"v6.6.99",
"v6.6.98",
"v6.6.97",
"v6.6.96",
"v6.6.95",
"v6.6.94",
"v6.6.93",
"v6.6.92",
"v6.6.91",
"v6.6.90",
"v6.6.89",
"v6.6.88",
"v6.6.87",
"v6.6.86",
"v6.6.85",
"v6.6.84",
"v6.6.83",
"v6.6.82",
"v6.6.81",
"v6.6.80",
"v6.6.79",
"v6.6.78",
"v6.6.77",
"v6.6.76",
"v6.6.75",
"v6.6.74",
"v6.6.73",
"v6.6.72",
"v6.6.71",
"v6.6.70",
"v6.6.69",
"v6.6.68",
"v6.6.67",
"v6.6.66",
"v6.6.65",
"v6.6.64",
"v6.6.63",
"v6.6.62",
"v6.6.61",
"v6.6.60",
"v6.6.59",
"v6.6.58",
"v6.6.57",
"v6.6.56",
"v6.6.55",
"v6.6.54",
"v6.6.53",
"v6.6.52",
"v6.6.51",
"v6.6.50",
"v6.6.49",
"v6.6.48",
"v6.6.47",
"v6.6.46",
"v6.6.45",
"v6.6.44",
"v6.6.43",
"v6.6.42",
"v6.6.41",
"v6.6.40",
"v6.6.39",
"v6.6.38",
"v6.6.37",
"v6.6.36",
"v6.6.35",
"v6.6.34",
"v6.6.33",
"v6.6.32"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64141.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "6.6.142"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.7.0"
},
{
"fixed": "6.12.92"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.9.0"
},
{
"fixed": "6.18.34"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.13.0"
},
{
"fixed": "7.0.11"
}
]
}
],
"package": {
"name": "Kernel",
"ecosystem": "Linux"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64141.json"
}
}
],
"modified": "2026-10-28T02:30:50.241244521Z",
"provider": "osv",
"references": [
"https://git.kernel.org/stable/c/0836081b394ca074d1b910f2b990ff7b4b4404c7",
"https://git.kernel.org/stable/c/4b83cbc4c15f09b000cc06f033f64b0824b6dc87",
"https://git.kernel.org/stable/c/af86896ca3239e25a6bd7d352213371265073d38",
"https://git.kernel.org/stable/c/cd5c1b75d2f454f625d7dc55bd3ae21d0855f6ad",
"https://git.kernel.org/stable/c/e43cb36d4d7827710cfcd48e95e29a507f0d87be",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64141.json",
"https://nvd.nist.gov/vuln/detail/CVE-2026-64141",
"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
],
"provider_metadata": {
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64141.json"
}
},
"related_cves": [
{
"value": "CVE-2026-64141",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 518665,
"published_at": "2026-07-19T15:40:33.89+00:00"
}