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CVE-2026-31609

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush() smbd_send_batch_flush() already calls smbd_free_send_io(), so we should not call it again after smbd_post_send() moved it to the batch list.

Severity
CRITICAL
CVSS score
9.8 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-24 15:16:40.160000
Last modified
2026-10-19 19:18:01.603000
View original CVE JSON
{
  "id": "CVE-2026-31609",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-04-24T15:16:40.160",
  "lastModified": "2026-10-19T19:18:01.603",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()\n\nsmbd_send_batch_flush() already calls smbd_free_send_io(),\nso we should not call it again after smbd_post_send()\nmoved it to the batch list."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/smb/client/smbdirect.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "cca0526ef2344cab6944d7f441fc24e152da031b",
              "lessThan": "a9940dcbe5cb92482c04efc7341039ddf7dbf607",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "37b5c06956183b65e6808b509cf637632016cdf7",
              "lessThan": "22b7c1c619d808aec4cad3dc42103345e370d107",
              "versionType": "git",
              "status": "affected"
            },
            {
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            },
            {
              "version": "6.18.11",
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              "versionType": "semver",
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            {
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            }
          ]
        },
        {
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          "product": "Linux",
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          "programFiles": [
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
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              "status": "affected"
            },
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              "version": "0",
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              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.24",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.19.14",
              "lessThanOrEqual": "6.19.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.0.1",
              "lessThanOrEqual": "7.0.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:11:13.445840Z",
          "id": "CVE-2026-31609",
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              "exploitation": "none"
            },
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          "role": "CISA Coordinator",
          "version": "2.0.3"
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  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-415"
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  "configurations": [
    {
      "nodes": [
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          "negate": false,
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      "url": "https://git.kernel.org/stable/c/22b7c1c619d808aec4cad3dc42103345e370d107",
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}