Vulnerability-Lookup

FKIE_CVE-2026-53383

Vulnerability from fkie_nvd - Published: 2026-07-19 12:16 - Updated: 2026-08-17 05:17

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: reject non-VALID session in compound request branch smb2_check_user_session() takes a shortcut for any operation that is not the first in a COMPOUND request: it reuses work->sess (the session bound by the first operation) and validates only the SessionId, then returns "valid". It never re-checks work->sess->state == SMB2_SESSION_VALID, and a SessionId of 0xFFFFFFFFFFFFFFFF (ULLONG_MAX, the MS-SMB2 related-operation value) skips even the id comparison. The standalone path (ksmbd_session_lookup_all() plus the SESSION_SETUP state machine) does enforce the VALID state; the compound branch bypasses all of it. A SESSION_SETUP carrying only an NTLM Type-1 (NtLmNegotiate) blob publishes a fresh SMB2_SESSION_IN_PROGRESS session whose sess->user is still NULL (->user is assigned later, by ntlm_authenticate()). Used as operation 1 of a COMPOUND with operation 2 = TREE_CONNECT (related, SessionId=ULLONG_MAX, \\host\IPC$), the tree-connect then runs on that IN_PROGRESS session and reaches ksmbd_ipc_tree_connect_request(), which dereferences user_name(sess->user) with sess->user == NULL (transport_ipc.c:687/701/704) -> remote NULL-pointer dereference and a kernel Oops that wedges the ksmbd worker for all clients. Reject any non-first compound operation that lands on a session which is not SMB2_SESSION_VALID, mirroring the validity the standalone lookup path enforces. SESSION_SETUP itself legitimately runs on an IN_PROGRESS session, but it is never carried as a non-first compound operation, so multi-leg authentication is unaffected by this check.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/06e1f05a1dbe8bbd054c0927b17fc0a61cc8bef7	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/25ff12b82a376ff5c4583102a63d2456a6b9ebb9	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/5f983b864d3d473ac533b2f4f44a1bbe5dcbccf4	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/609ca17d869d04ba249e32cdcbf13c0b1c66f43c	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7cad3ceaf679c55bc9946685dacafce78ce6b51a	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/8f0302fb691537d33ec8f668565257ea9d340ffe	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d2bbbb6c55812220fee5d801c275cc267ea3cbeb	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/fc578523a72cb8b329d32070b95898e81613cc3f	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.4

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
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              "status": "affected",
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        {
          "defaultStatus": "affected",
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            },
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              "status": "unaffected",
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              "status": "unaffected",
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            },
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              "status": "unaffected",
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              "status": "unaffected",
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            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
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              "status": "unaffected",
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              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
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            {
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            {
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              "vulnerable": true
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          ],
          "negate": false,
          "operator": "OR"
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      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: reject non-VALID session in compound request branch\n\nsmb2_check_user_session() takes a shortcut for any operation that is not\nthe first in a COMPOUND request: it reuses work-\u003esess (the session bound by\nthe first operation) and validates only the SessionId, then returns\n\"valid\". It never re-checks work-\u003esess-\u003estate == SMB2_SESSION_VALID, and a\nSessionId of 0xFFFFFFFFFFFFFFFF (ULLONG_MAX, the MS-SMB2 related-operation\nvalue) skips even the id comparison. The standalone path\n(ksmbd_session_lookup_all() plus the SESSION_SETUP state machine) does\nenforce the VALID state; the compound branch bypasses all of it.\n\nA SESSION_SETUP carrying only an NTLM Type-1 (NtLmNegotiate) blob publishes\na fresh SMB2_SESSION_IN_PROGRESS session whose sess-\u003euser is still NULL\n(-\u003euser is assigned later, by ntlm_authenticate()). Used as operation 1 of\na COMPOUND with operation 2 = TREE_CONNECT (related, SessionId=ULLONG_MAX,\n\\\\host\\IPC$), the tree-connect then runs on that IN_PROGRESS session and\nreaches ksmbd_ipc_tree_connect_request(), which dereferences\nuser_name(sess-\u003euser) with sess-\u003euser == NULL (transport_ipc.c:687/701/704)\n-\u003e remote NULL-pointer dereference and a kernel Oops that wedges the ksmbd\nworker for all clients.\n\nReject any non-first compound operation that lands on a session which is\nnot SMB2_SESSION_VALID, mirroring the validity the standalone lookup path\nenforces. SESSION_SETUP itself legitimately runs on an IN_PROGRESS session,\nbut it is never carried as a non-first compound operation, so multi-leg\nauthentication is unaffected by this check."
    }
  ],
  "id": "CVE-2026-53383",
  "lastModified": "2026-08-17T05:17:12.240",
  "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"
      }
    ]
  },
  "published": "2026-07-19T12:16:49.117",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/06e1f05a1dbe8bbd054c0927b17fc0a61cc8bef7"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/25ff12b82a376ff5c4583102a63d2456a6b9ebb9"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/5f983b864d3d473ac533b2f4f44a1bbe5dcbccf4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/609ca17d869d04ba249e32cdcbf13c0b1c66f43c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/7cad3ceaf679c55bc9946685dacafce78ce6b51a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/8f0302fb691537d33ec8f668565257ea9d340ffe"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/d2bbbb6c55812220fee5d801c275cc267ea3cbeb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/fc578523a72cb8b329d32070b95898e81613cc3f"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2026-53383 (GCVE-0-2026-53383)

Vulnerability from cvelistv5 – Published: 2026-07-19 11:59 – Updated: 2026-08-17 04:50

Title

ksmbd: reject non-VALID session in compound request branch

Summary

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Assigner

Linux mitre root

References

8 references

URL	Tags
https://git.kernel.org/stable/c/25ff12b82a376ff5c…
https://git.kernel.org/stable/c/fc578523a72cb8b32…
https://git.kernel.org/stable/c/d2bbbb6c55812220f…
https://git.kernel.org/stable/c/8f0302fb691537d33…
https://git.kernel.org/stable/c/7cad3ceaf679c55bc…
https://git.kernel.org/stable/c/06e1f05a1dbe8bbd0…
https://git.kernel.org/stable/c/5f983b864d3d473ac…
https://git.kernel.org/stable/c/609ca17d869d04ba2…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: eb947403518ea3d93f6d89264bb1f5416bb0c7d0 , < 25ff12b82a376ff5c4583102a63d2456a6b9ebb9 (git) Affected: 854156d12caa9d36de1cf5f084591c7686cc8a9d , < fc578523a72cb8b329d32070b95898e81613cc3f (git) Affected: 5005bcb4219156f1bf7587b185080ec1da08518e , < d2bbbb6c55812220fee5d801c275cc267ea3cbeb (git) Affected: 5005bcb4219156f1bf7587b185080ec1da08518e , < 8f0302fb691537d33ec8f668565257ea9d340ffe (git) Affected: 5005bcb4219156f1bf7587b185080ec1da08518e , < 7cad3ceaf679c55bc9946685dacafce78ce6b51a (git) Affected: 5005bcb4219156f1bf7587b185080ec1da08518e , < 06e1f05a1dbe8bbd054c0927b17fc0a61cc8bef7 (git) Affected: 5005bcb4219156f1bf7587b185080ec1da08518e , < 5f983b864d3d473ac533b2f4f44a1bbe5dcbccf4 (git) Affected: 5005bcb4219156f1bf7587b185080ec1da08518e , < 609ca17d869d04ba249e32cdcbf13c0b1c66f43c (git) Affected: d1066c1b3663401cd23c0d6e60cdae750ce00c0f (git) Affected: 5.15.121 , < 5.15.211 (semver) Affected: 6.1.36 , < 6.1.177 (semver) Affected: 6.3.10 , < 6.4 (semver)
Linux	Linux	Affected: 6.4 Unaffected: 0 , < 6.4 (semver) Unaffected: 5.15.211 , ≤ 5.15.* (semver) Unaffected: 6.1.177 , ≤ 6.1.* (semver) Unaffected: 6.6.144 , ≤ 6.6.* (semver) Unaffected: 6.12.95 , ≤ 6.12.* (semver) Unaffected: 6.18.37 , ≤ 6.18.* (semver) Unaffected: 7.0.14 , ≤ 7.0.* (semver) Unaffected: 7.1.2 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "25ff12b82a376ff5c4583102a63d2456a6b9ebb9",
              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "fc578523a72cb8b329d32070b95898e81613cc3f",
              "status": "affected",
              "version": "854156d12caa9d36de1cf5f084591c7686cc8a9d",
              "versionType": "git"
            },
            {
              "lessThan": "d2bbbb6c55812220fee5d801c275cc267ea3cbeb",
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              "version": "5005bcb4219156f1bf7587b185080ec1da08518e",
              "versionType": "git"
            },
            {
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              "versionType": "git"
            },
            {
              "lessThan": "7cad3ceaf679c55bc9946685dacafce78ce6b51a",
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              "versionType": "git"
            },
            {
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              "versionType": "git"
            },
            {
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              "versionType": "git"
            },
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            },
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              "status": "affected",
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              "versionType": "semver"
            },
            {
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              "status": "affected",
              "version": "6.1.36",
              "versionType": "semver"
            },
            {
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              "status": "affected",
              "version": "6.3.10",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.4"
            },
            {
              "lessThan": "6.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.211",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.177",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.144",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.95",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.37",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.211",
                  "versionStartIncluding": "5.15.121",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.177",
                  "versionStartIncluding": "6.1.36",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.144",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.95",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.37",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.14",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.2",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.3.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: reject non-VALID session in compound request branch\n\nsmb2_check_user_session() takes a shortcut for any operation that is not\nthe first in a COMPOUND request: it reuses work-\u003esess (the session bound by\nthe first operation) and validates only the SessionId, then returns\n\"valid\". It never re-checks work-\u003esess-\u003estate == SMB2_SESSION_VALID, and a\nSessionId of 0xFFFFFFFFFFFFFFFF (ULLONG_MAX, the MS-SMB2 related-operation\nvalue) skips even the id comparison. The standalone path\n(ksmbd_session_lookup_all() plus the SESSION_SETUP state machine) does\nenforce the VALID state; the compound branch bypasses all of it.\n\nA SESSION_SETUP carrying only an NTLM Type-1 (NtLmNegotiate) blob publishes\na fresh SMB2_SESSION_IN_PROGRESS session whose sess-\u003euser is still NULL\n(-\u003euser is assigned later, by ntlm_authenticate()). Used as operation 1 of\na COMPOUND with operation 2 = TREE_CONNECT (related, SessionId=ULLONG_MAX,\n\\\\host\\IPC$), the tree-connect then runs on that IN_PROGRESS session and\nreaches ksmbd_ipc_tree_connect_request(), which dereferences\nuser_name(sess-\u003euser) with sess-\u003euser == NULL (transport_ipc.c:687/701/704)\n-\u003e remote NULL-pointer dereference and a kernel Oops that wedges the ksmbd\nworker for all clients.\n\nReject any non-first compound operation that lands on a session which is\nnot SMB2_SESSION_VALID, mirroring the validity the standalone lookup path\nenforces. SESSION_SETUP itself legitimately runs on an IN_PROGRESS session,\nbut it is never carried as a non-first compound operation, so multi-leg\nauthentication is unaffected by this check."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The bug is in ksmbd\u0027s SMB2 compound-request handler, reachable by any remote attacker who can send crafted SMB2 packets to TCP port 445 on a host running the in-kernel SMB server.\nAC:L - An attacker can reliably trigger the bug by sending a compound SMB2 request with SESSION_SETUP (NTLM Type-1 only) as the first operation and TREE_CONNECT (SessionId=0xFFFFFFFFFFFFFFFF, \\\\host\\IPC$) as the second; no special timing, memory layout, or victim state is required.\nPR:N - Exploitation requires only network access to ksmbd during the SMB2 authentication handshake, before sess-\u003euser is assigned; no Linux local account, capability, or prior authenticated OS session is needed.\nUI:N - No victim user action (opening files, mounting shares, clicking links) is required; the attacker triggers the crash solely by sending malicious SMB2 protocol traffic.\nS:U - The impact is a kernel oops and ksmbd worker disruption within the kernel/SMB server security authority; it does not cross a VM, container, or IOMMU boundary.\nC:N - The failure is a NULL pointer dereference on sess-\u003euser in ksmbd_ipc_tree_connect_request() when user_name(sess-\u003euser) is called with sess-\u003euser == NULL; this is a pure crash with no information disclosure.\nI:N - The bug causes a NULL pointer dereference only; there is no memory corruption, arbitrary write, or code-execution primitive\u2014only a kernel fault.\nA:H - The NULL dereference causes a kernel oops that wedges the shared ksmbd-io workqueue worker, denying SMB service to all clients connected through that worker and potentially panicking the host if panic_on_oops is enabled."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:50:33.785Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/25ff12b82a376ff5c4583102a63d2456a6b9ebb9"
        },
        {
          "url": "https://git.kernel.org/stable/c/fc578523a72cb8b329d32070b95898e81613cc3f"
        },
        {
          "url": "https://git.kernel.org/stable/c/d2bbbb6c55812220fee5d801c275cc267ea3cbeb"
        },
        {
          "url": "https://git.kernel.org/stable/c/8f0302fb691537d33ec8f668565257ea9d340ffe"
        },
        {
          "url": "https://git.kernel.org/stable/c/7cad3ceaf679c55bc9946685dacafce78ce6b51a"
        },
        {
          "url": "https://git.kernel.org/stable/c/06e1f05a1dbe8bbd054c0927b17fc0a61cc8bef7"
        },
        {
          "url": "https://git.kernel.org/stable/c/5f983b864d3d473ac533b2f4f44a1bbe5dcbccf4"
        },
        {
          "url": "https://git.kernel.org/stable/c/609ca17d869d04ba249e32cdcbf13c0b1c66f43c"
        }
      ],
      "title": "ksmbd: reject non-VALID session in compound request branch",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-53383",
    "datePublished": "2026-07-19T11:59:31.616Z",
    "dateReserved": "2026-06-09T07:44:35.401Z",
    "dateUpdated": "2026-08-17T04:50:33.785Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

FKIE_CVE-2026-53383

CVE-2026-53383 (GCVE-0-2026-53383)

Tags

Sightings

Nomenclature