Vulnerability-Lookup

GHSA-J2X9-QG6Q-8WG7

Vulnerability from github – Published: 2025-08-16 15:30 – Updated: 2025-11-18 18:32

Details

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: validate command request size

In commit 2b9b8f3b68ed ("ksmbd: validate command payload size"), except for SMB2_OPLOCK_BREAK_HE command, the request size of other commands is not checked, it's not expected. Fix it by add check for request size of other commands.

Severity

5.5 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2023-4515"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-08-16T14:15:27Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: validate command request size\n\nIn commit 2b9b8f3b68ed (\"ksmbd: validate command payload size\"), except\nfor SMB2_OPLOCK_BREAK_HE command, the request size of other commands\nis not checked, it\u0027s not expected. Fix it by add check for request\nsize of other commands.",
  "id": "GHSA-j2x9-qg6q-8wg7",
  "modified": "2025-11-18T18:32:49Z",
  "published": "2025-08-16T15:30:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-4515"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/595679098bdcdbfbba91ebe07a2f7f208df93870"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5aa4fda5aa9c2a5a7bac67b4a12b089ab81fee3c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c6bef3bc30fd4a175aef846b7d928a6c40d091cd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ff7236b66d69582f90cf5616e63cfc3dc18142bb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2023-4515 (GCVE-0-2023-4515)

Vulnerability from cvelistv5 – Published: 2025-08-16 13:25 – Updated: 2026-08-05 09:09

Title

ksmbd: validate command request size

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate command request size In commit 2b9b8f3b68ed ("ksmbd: validate command payload size"), except for SMB2_OPLOCK_BREAK_HE command, the request size of other commands is not checked, it's not expected. Fix it by add check for request size of other commands.

Severity

9.1 (Critical)


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

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/595679098bdcdbfbb…
https://git.kernel.org/stable/c/c6bef3bc30fd4a175…
https://git.kernel.org/stable/c/ff7236b66d69582f9…
https://git.kernel.org/stable/c/5aa4fda5aa9c2a5a7…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 35f450f54dca1519bb24faacd0428db09f89a11f , < 595679098bdcdbfbba91ebe07a2f7f208df93870 (git) Affected: 9650cf70ec9d94ff34daa088b643229231723c26 , < c6bef3bc30fd4a175aef846b7d928a6c40d091cd (git) Affected: 2b9b8f3b68edb3d67d79962f02e26dbb5ae3808d , < ff7236b66d69582f90cf5616e63cfc3dc18142bb (git) Affected: 2b9b8f3b68edb3d67d79962f02e26dbb5ae3808d , < 5aa4fda5aa9c2a5a7bac67b4a12b089ab81fee3c (git) Affected: 768caf4019f0391c0b6452afe34cea1704133f7b (git) Affected: 5.15.121 , < 5.15.127 (semver) Affected: 6.1.36 , < 6.1.46 (semver) Affected: 6.3.10 , < 6.4 (semver)
Linux	Linux	Affected: 6.4 Unaffected: 0 , < 6.4 (semver) Unaffected: 5.15.127 , ≤ 5.15.* (semver) Unaffected: 6.1.46 , ≤ 6.1.* (semver) Unaffected: 6.4.11 , ≤ 6.4.* (semver) Unaffected: 6.5 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2misc.c"
          ],
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          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "595679098bdcdbfbba91ebe07a2f7f208df93870",
              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "c6bef3bc30fd4a175aef846b7d928a6c40d091cd",
              "status": "affected",
              "version": "9650cf70ec9d94ff34daa088b643229231723c26",
              "versionType": "git"
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            {
              "lessThan": "ff7236b66d69582f90cf5616e63cfc3dc18142bb",
              "status": "affected",
              "version": "2b9b8f3b68edb3d67d79962f02e26dbb5ae3808d",
              "versionType": "git"
            },
            {
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              "status": "affected",
              "version": "2b9b8f3b68edb3d67d79962f02e26dbb5ae3808d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "768caf4019f0391c0b6452afe34cea1704133f7b",
              "versionType": "git"
            },
            {
              "lessThan": "5.15.127",
              "status": "affected",
              "version": "5.15.121",
              "versionType": "semver"
            },
            {
              "lessThan": "6.1.46",
              "status": "affected",
              "version": "6.1.36",
              "versionType": "semver"
            },
            {
              "lessThan": "6.4",
              "status": "affected",
              "version": "6.3.10",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2misc.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": "5.15.127",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.46",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.4.*",
              "status": "unaffected",
              "version": "6.4.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.5",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.127",
                  "versionStartIncluding": "5.15.121",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "6.1.36",
                  "vulnerable": true
                },
                {
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                  "versionStartIncluding": "6.4",
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                },
                {
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                {
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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\nksmbd: validate command request size\n\nIn commit 2b9b8f3b68ed (\"ksmbd: validate command payload size\"), except\nfor SMB2_OPLOCK_BREAK_HE command, the request size of other commands\nis not checked, it\u0027s not expected. Fix it by add check for request\nsize of other commands."
        }
      ],
      "metrics": [
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          "cvssV3_1": {
            "baseScore": 9.1,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The vulnerable code is in ksmbd (fs/smb/server/), the in-kernel SMB server reached over TCP/445; a remote peer triggers it by sending a crafted SMB2 PDU that fails StructureSize2 validation.\nAC:L - An attacker fully controls StructureSize2 and the RFC1002 PDU length and can reliably send a short pre-auth SESSION_SETUP (e.g. StructureSize2=1 with pdu_size=68) that passes the incomplete check and OOBs in smb2_get_data_area_len; no race or external condition is required.\nPR:N - ksmbd_smb2_check_message runs for SMB2_NEGOTIATE, SMB2_SESSION_SETUP, and SMB2_ECHO, which smb2_check_user_session explicitly allows without a session, so the OOB is reachable before any credential verification.\nUI:N - Exploitation requires only attacker-sent SMB2 packets to a listening ksmbd instance; no victim user action is needed.\nS:U - Impact stays within the host kernel/ksmbd security authority (heap OOB read/DoS); this is not a VM escape, IOMMU bypass, or other cross-authority boundary change.\nC:H - Missing StructureSize2 matching allows slab out-of-bounds reads of fixed command fields (and subsequent use of those values as security-blob offset/length), which can disclose adjacent kernel heap contents under standard grooming; per guidance OOB reads score C:H.\nI:N - The defect is an out-of-bounds read from incomplete request-size validation; unlike related ksmbd heap overflows there is no demonstrated out-of-bounds write or direct integrity/control-flow primitive from this bug alone.\nA:H - The slab OOB read can fault under KFENCE/DEBUG_PAGEALLOC or panic under KASAN (as in the related KASAN report for the incomplete parent fix), and the attacker can retrigger it pre-authentication at will."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:09:51.240Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/595679098bdcdbfbba91ebe07a2f7f208df93870"
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          "url": "https://git.kernel.org/stable/c/c6bef3bc30fd4a175aef846b7d928a6c40d091cd"
        },
        {
          "url": "https://git.kernel.org/stable/c/ff7236b66d69582f90cf5616e63cfc3dc18142bb"
        },
        {
          "url": "https://git.kernel.org/stable/c/5aa4fda5aa9c2a5a7bac67b4a12b089ab81fee3c"
        }
      ],
      "title": "ksmbd: validate command request size",
      "x_generator": {
        "engine": "bippy-1.2.0"
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    }
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-4515",
    "datePublished": "2025-08-16T13:25:50.562Z",
    "dateReserved": "2023-08-24T10:34:48.702Z",
    "dateUpdated": "2026-08-05T09:09:51.240Z",
    "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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.