Vulnerability-Lookup

GHSA-P37W-XHV5-6C8J

Vulnerability from github – Published: 2026-04-24 15:32 – Updated: 2026-04-24 15:32

Details

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

smb: client: fix off-by-8 bounds check in check_wsl_eas()

The bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA name and value, but ea_data sits at offset sizeof(struct smb2_file_full_ea_info) = 8 from ea, not at offset 0. The strncmp() later reads ea->ea_data[0..nlen-1] and the value bytes follow at ea_data[nlen+1..nlen+vlen], so the actual end is ea->ea_data + nlen + 1 + vlen. Isn't pointer math fun?

The earlier check (u8 )ea > end - sizeof(ea) only guarantees the 8-byte header is in bounds, but since the last EA is placed within 8 bytes of the end of the response, the name and value bytes are read past the end of iov.

Fix this mess all up by using ea->ea_data as the base for the bounds check.

An "untrusted" server can use this to leak up to 8 bytes of kernel heap into the EA name comparison and influence which WSL xattr the data is interpreted as.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-31614"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-24T15:16:40Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix off-by-8 bounds check in check_wsl_eas()\n\nThe bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA\nname and value, but ea_data sits at offset sizeof(struct\nsmb2_file_full_ea_info) = 8 from ea, not at offset 0.  The strncmp()\nlater reads ea-\u003eea_data[0..nlen-1] and the value bytes follow at\nea_data[nlen+1..nlen+vlen], so the actual end is ea-\u003eea_data + nlen + 1\n+ vlen.  Isn\u0027t pointer math fun?\n\nThe earlier check (u8 *)ea \u003e end - sizeof(*ea) only guarantees the\n8-byte header is in bounds, but since the last EA is placed within 8\nbytes of the end of the response, the name and value bytes are read past\nthe end of iov.\n\nFix this mess all up by using ea-\u003eea_data as the base for the bounds\ncheck.\n\nAn \"untrusted\" server can use this to leak up to 8 bytes of kernel heap\ninto the EA name comparison and influence which WSL xattr the data is\ninterpreted as.",
  "id": "GHSA-p37w-xhv5-6c8j",
  "modified": "2026-04-24T15:32:35Z",
  "published": "2026-04-24T15:32:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31614"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5cc0574c84aa73946ade587c41e81757b8b01cb5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a893f1757d9a4009e4a8d7ceb2312142fe29cea4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b2b76d09a64c538c57006180103fc1841e8cfa66"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-31614 (GCVE-0-2026-31614)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:42 – Updated: 2026-04-25 05:48

Title

smb: client: fix off-by-8 bounds check in check_wsl_eas()

Summary

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix off-by-8 bounds check in check_wsl_eas() The bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA name and value, but ea_data sits at offset sizeof(struct smb2_file_full_ea_info) = 8 from ea, not at offset 0. The strncmp() later reads ea->ea_data[0..nlen-1] and the value bytes follow at ea_data[nlen+1..nlen+vlen], so the actual end is ea->ea_data + nlen + 1 + vlen. Isn't pointer math fun? The earlier check (u8 *)ea > end - sizeof(*ea) only guarantees the 8-byte header is in bounds, but since the last EA is placed within 8 bytes of the end of the response, the name and value bytes are read past the end of iov. Fix this mess all up by using ea->ea_data as the base for the bounds check. An "untrusted" server can use this to leak up to 8 bytes of kernel heap into the EA name comparison and influence which WSL xattr the data is interpreted as.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/5cc0574c84aa73946…
	https://git.kernel.org/stable/c/b2b76d09a64c538c5…
	https://git.kernel.org/stable/c/ba3ad159aa61810bb…
	https://git.kernel.org/stable/c/a893f1757d9a4009e…

Impacted products

Vendor

Product

Version

Linux

Affected: ea41367b2a602f602ea6594fc4a310520dcc64f4 , < 5cc0574c84aa73946ade587c41e81757b8b01cb5 (git)
Affected: ea41367b2a602f602ea6594fc4a310520dcc64f4 , < b2b76d09a64c538c57006180103fc1841e8cfa66 (git)
Affected: ea41367b2a602f602ea6594fc4a310520dcc64f4 , < ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18 (git)
Affected: ea41367b2a602f602ea6594fc4a310520dcc64f4 , < a893f1757d9a4009e4a8d7ceb2312142fe29cea4 (git)
Affected: 7449d736bbbd160c76b01b8fcdf72f58a8757d4b (git)

Linux

Affected: 6.9
Unaffected: 0 , < 6.9 (semver)
Unaffected: 6.12.83 , ≤ 6.12.* (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0.1 , ≤ 7.0.* (semver)

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2inode.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5cc0574c84aa73946ade587c41e81757b8b01cb5",
              "status": "affected",
              "version": "ea41367b2a602f602ea6594fc4a310520dcc64f4",
              "versionType": "git"
            },
            {
              "lessThan": "b2b76d09a64c538c57006180103fc1841e8cfa66",
              "status": "affected",
              "version": "ea41367b2a602f602ea6594fc4a310520dcc64f4",
              "versionType": "git"
            },
            {
              "lessThan": "ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18",
              "status": "affected",
              "version": "ea41367b2a602f602ea6594fc4a310520dcc64f4",
              "versionType": "git"
            },
            {
              "lessThan": "a893f1757d9a4009e4a8d7ceb2312142fe29cea4",
              "status": "affected",
              "version": "ea41367b2a602f602ea6594fc4a310520dcc64f4",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "7449d736bbbd160c76b01b8fcdf72f58a8757d4b",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2inode.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.9"
            },
            {
              "lessThan": "6.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.83",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.24",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.1",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.83",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.24",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.14",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.1",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.6.32",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix off-by-8 bounds check in check_wsl_eas()\n\nThe bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA\nname and value, but ea_data sits at offset sizeof(struct\nsmb2_file_full_ea_info) = 8 from ea, not at offset 0.  The strncmp()\nlater reads ea-\u003eea_data[0..nlen-1] and the value bytes follow at\nea_data[nlen+1..nlen+vlen], so the actual end is ea-\u003eea_data + nlen + 1\n+ vlen.  Isn\u0027t pointer math fun?\n\nThe earlier check (u8 *)ea \u003e end - sizeof(*ea) only guarantees the\n8-byte header is in bounds, but since the last EA is placed within 8\nbytes of the end of the response, the name and value bytes are read past\nthe end of iov.\n\nFix this mess all up by using ea-\u003eea_data as the base for the bounds\ncheck.\n\nAn \"untrusted\" server can use this to leak up to 8 bytes of kernel heap\ninto the EA name comparison and influence which WSL xattr the data is\ninterpreted as."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-25T05:48:21.841Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5cc0574c84aa73946ade587c41e81757b8b01cb5"
        },
        {
          "url": "https://git.kernel.org/stable/c/b2b76d09a64c538c57006180103fc1841e8cfa66"
        },
        {
          "url": "https://git.kernel.org/stable/c/ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18"
        },
        {
          "url": "https://git.kernel.org/stable/c/a893f1757d9a4009e4a8d7ceb2312142fe29cea4"
        }
      ],
      "title": "smb: client: fix off-by-8 bounds check in check_wsl_eas()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31614",
    "datePublished": "2026-04-24T14:42:34.153Z",
    "dateReserved": "2026-03-09T15:48:24.123Z",
    "dateUpdated": "2026-04-25T05:48:21.841Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

GHSA-P37W-XHV5-6C8J

CVE-2026-31614 (GCVE-0-2026-31614)

Tags

Sightings

Nomenclature