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CVE-2026-63971

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: sctp: fix race between sctp_wait_for_connect and peeloff sctp_wait_for_connect() drops and re-acquires the socket lock while waiting for the association to reach ESTABLISHED state. During this window, another thread can peeloff the association to a new socket via getsockopt(SCTP_SOCKOPT_PEELOFF), changing asoc->base.sk. After re-acquiring the old socket lock, sctp_wait_for_connect() returns success without noticing the migration — the caller then accesses the association under the wrong lock in sctp_datamsg_from_user(). Add the same sk != asoc->base.sk check that sctp_wait_for_sndbuf() already has, returning an error if the association was migrated while we slept.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-19 16:17:16.163000
Last modified
2026-10-19 21:17:14.660000
View original CVE JSON 
{
  "id": "CVE-2026-63971",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-19T16:17:16.163",
  "lastModified": "2026-10-19T21:17:14.660",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: fix race between sctp_wait_for_connect and peeloff\n\nsctp_wait_for_connect() drops and re-acquires the socket lock while\nwaiting for the association to reach ESTABLISHED state. During this\nwindow, another thread can peeloff the association to a new socket via\ngetsockopt(SCTP_SOCKOPT_PEELOFF), changing asoc->base.sk. After\nre-acquiring the old socket lock, sctp_wait_for_connect() returns\nsuccess without noticing the migration — the caller then accesses\nthe association under the wrong lock in sctp_datamsg_from_user().\n\nAdd the same sk != asoc->base.sk check that sctp_wait_for_sndbuf()\nalready has, returning an error if the association was migrated while\nwe slept."
    }
  ],
  "affected": [
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      "affectedData": [
        {
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          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
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              "versionType": "original_commit_for_fix",
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  "metrics": {
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
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        "ssvcData": {
          "timestamp": "2026-10-16T15:34:18.318567Z",
          "id": "CVE-2026-63971",
          "options": [
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              "exploitation": "none"
            },
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            },
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              "technicalImpact": "total"
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          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
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  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
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  ],
  "configurations": [
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          "negate": false,
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}