Skip to content
Heist/ feed
Back to feed
CriticalFix available

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()

Type: advisorySources: OSV

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free.

Products
Kernel
Affected versions
Not specified
Fixed versions
6.12.78, 6.18.19, 6.19.9, 6.6.130
CVEs
CVE-2026-43379
Confirmed fixed CVEs
Not specified
Updated in this feed
5 Nov 2026, 03:17 UTC · Revision 1

Source evidence

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()

core-osv · Original source

Published 8 May 2026, 14:21 UTC

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free.

osv:CVE-2026-43379

Kernel

Fixed versions: 6.6.130, 6.12.78, 6.18.19, 6.19.9

Complete source record
{
  "id": "46078dbda633be31b85eba18ccafc1a75fefa0aef0e0569f20bd231ced8851d9",
  "url": "https://osv.dev/vulnerability/CVE-2026-43379",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free.",
    "evidence": "osv:CVE-2026-43379",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.130",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.78",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.19",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.19.9",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-43379",
      "aliases": [
        "CVE-2026-43379"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "27b40b7bfcd121fe13a150ffe11957630cf49246"
                },
                {
                  "fixed": "bf4d66d72e4a9e268c1012c331ce9eaedb5e2086"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "5fb282ba4fef8985a5acf2b32681f2ec07732561"
                },
                {
                  "fixed": "960699317d39f46611f4ebeb69edc567c1f4e6b6"
                },
                {
                  "fixed": "dbbd328cf58261ca239756fe1c0d10c9518d3399"
                },
                {
                  "fixed": "b3568347c51c46e2cabc356bc34676df98296619"
                },
                {
                  "fixed": "eac3361e3d5dd8067b3258c69615888eb45e9f25"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "6.6.32"
                },
                {
                  "fixed": "6.6.130"
                }
              ]
            }
          ],
          "versions": [
            "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-2026-43379.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "6.6.130"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.78"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.9.0"
                },
                {
                  "fixed": "6.18.19"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.19.9"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-43379.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:42.260368865Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6",
        "https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619",
        "https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086",
        "https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399",
        "https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43379.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-43379",
        "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/2026/43xxx/CVE-2026-43379.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-43379",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 509796,
  "published_at": "2026-05-08T14:21:28.027+00:00"
}