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FKIE_CVE-2025-40090

Vulnerability from fkie_nvd - Published: 2025-10-30 10:15 - Updated: 2026-07-30 06:24
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix recursive locking in RPC handle list access Since commit 305853cce3794 ("ksmbd: Fix race condition in RPC handle list access"), ksmbd_session_rpc_method() attempts to lock sess->rpc_lock. This causes hung connections / tasks when a client attempts to open a named pipe. Using Samba's rpcclient tool: $ rpcclient //192.168.1.254 -U user%password $ rpcclient $> srvinfo <connection hung here> Kernel side: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:D stack:0 pid:5021 tgid:5021 ppid:2 flags:0x00200000 Workqueue: ksmbd-io handle_ksmbd_work Call trace: __schedule from schedule+0x3c/0x58 schedule from schedule_preempt_disabled+0xc/0x10 schedule_preempt_disabled from rwsem_down_read_slowpath+0x1b0/0x1d8 rwsem_down_read_slowpath from down_read+0x28/0x30 down_read from ksmbd_session_rpc_method+0x18/0x3c ksmbd_session_rpc_method from ksmbd_rpc_open+0x34/0x68 ksmbd_rpc_open from ksmbd_session_rpc_open+0x194/0x228 ksmbd_session_rpc_open from create_smb2_pipe+0x8c/0x2c8 create_smb2_pipe from smb2_open+0x10c/0x27ac smb2_open from handle_ksmbd_work+0x238/0x3dc handle_ksmbd_work from process_scheduled_works+0x160/0x25c process_scheduled_works from worker_thread+0x16c/0x1e8 worker_thread from kthread+0xa8/0xb8 kthread from ret_from_fork+0x14/0x38 Exception stack(0x8529ffb0 to 0x8529fff8) The task deadlocks because the lock is already held: ksmbd_session_rpc_open down_write(&sess->rpc_lock) ksmbd_rpc_open ksmbd_session_rpc_method down_read(&sess->rpc_lock) <-- deadlock Adjust ksmbd_session_rpc_method() callers to take the lock when necessary.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1891abe832cbf5a11039e088766131d0f1642d02Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3412fbd81b46b9cfae013817b61d4bbd27e09e36Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4602b8cee1481dbb896182e5cb1e8cf12910e9e7Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5493571f4351f74e11db9943e98a07c56467cf7ePatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/88f170814fea74911ceab798a43cbd7c5599bed4Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 6.18
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/mgmt/user_session.c",
            "fs/smb/server/smb2pdu.c",
            "fs/smb/server/transport_ipc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5493571f4351f74e11db9943e98a07c56467cf7e",
              "status": "affected",
              "version": "69674b029002b1d90b655f014bdf64f404efa54d",
              "versionType": "git"
            },
            {
              "lessThan": "1891abe832cbf5a11039e088766131d0f1642d02",
              "status": "affected",
              "version": "6b615a8fb3af0baf8126cde3d4fee97d57222ffc",
              "versionType": "git"
            },
            {
              "lessThan": "4602b8cee1481dbb896182e5cb1e8cf12910e9e7",
              "status": "affected",
              "version": "5cc679ba0f4505936124cd4179ba66bb0a4bd9f3",
              "versionType": "git"
            },
            {
              "lessThan": "3412fbd81b46b9cfae013817b61d4bbd27e09e36",
              "status": "affected",
              "version": "6bd7e0e55dcea2cf0d391bbc21c2eb069b4be3e1",
              "versionType": "git"
            },
            {
              "lessThan": "88f170814fea74911ceab798a43cbd7c5599bed4",
              "status": "affected",
              "version": "305853cce379407090a73b38c5de5ba748893aee",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/mgmt/user_session.c",
            "fs/smb/server/smb2pdu.c",
            "fs/smb/server/transport_ipc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "6.12.55",
              "status": "affected",
              "version": "6.12.53",
              "versionType": "semver"
            },
            {
              "lessThan": "6.17.5",
              "status": "affected",
              "version": "6.17.3",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "E4EB1667-C055-4880-911F-BD74B6375984",
              "versionEndExcluding": "6.12.55",
              "versionStartIncluding": "6.12.53",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "99358CF3-A8B9-4638-A2ED-6200D3371019",
              "versionEndExcluding": "6.17.5",
              "versionStartIncluding": "6.17.3",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.18:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "DD01661D-DFC8-4B6D-80E7-46D203CC4565",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix recursive locking in RPC handle list access\n\nSince commit 305853cce3794 (\"ksmbd: Fix race condition in RPC handle list\naccess\"), ksmbd_session_rpc_method() attempts to lock sess-\u003erpc_lock.\n\nThis causes hung connections / tasks when a client attempts to open\na named pipe. Using Samba\u0027s rpcclient tool:\n\n $ rpcclient //192.168.1.254 -U user%password\n $ rpcclient $\u003e srvinfo\n \u003cconnection hung here\u003e\n\nKernel side:\n  \"echo 0 \u003e /proc/sys/kernel/hung_task_timeout_secs\" disables this message.\n  task:kworker/0:0 state:D stack:0 pid:5021 tgid:5021 ppid:2 flags:0x00200000\n  Workqueue: ksmbd-io handle_ksmbd_work\n  Call trace:\n  __schedule from schedule+0x3c/0x58\n  schedule from schedule_preempt_disabled+0xc/0x10\n  schedule_preempt_disabled from rwsem_down_read_slowpath+0x1b0/0x1d8\n  rwsem_down_read_slowpath from down_read+0x28/0x30\n  down_read from ksmbd_session_rpc_method+0x18/0x3c\n  ksmbd_session_rpc_method from ksmbd_rpc_open+0x34/0x68\n  ksmbd_rpc_open from ksmbd_session_rpc_open+0x194/0x228\n  ksmbd_session_rpc_open from create_smb2_pipe+0x8c/0x2c8\n  create_smb2_pipe from smb2_open+0x10c/0x27ac\n  smb2_open from handle_ksmbd_work+0x238/0x3dc\n  handle_ksmbd_work from process_scheduled_works+0x160/0x25c\n  process_scheduled_works from worker_thread+0x16c/0x1e8\n  worker_thread from kthread+0xa8/0xb8\n  kthread from ret_from_fork+0x14/0x38\n  Exception stack(0x8529ffb0 to 0x8529fff8)\n\nThe task deadlocks because the lock is already held:\n  ksmbd_session_rpc_open\n    down_write(\u0026sess-\u003erpc_lock)\n    ksmbd_rpc_open\n      ksmbd_session_rpc_method\n        down_read(\u0026sess-\u003erpc_lock)   \u003c-- deadlock\n\nAdjust ksmbd_session_rpc_method() callers to take the lock when necessary."
    }
  ],
  "id": "CVE-2025-40090",
  "lastModified": "2026-07-30T06:24:10.810",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2025-10-30T10:15:33.537",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/1891abe832cbf5a11039e088766131d0f1642d02"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3412fbd81b46b9cfae013817b61d4bbd27e09e36"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/4602b8cee1481dbb896182e5cb1e8cf12910e9e7"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/5493571f4351f74e11db9943e98a07c56467cf7e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/88f170814fea74911ceab798a43cbd7c5599bed4"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-674"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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