CVE-2026-63971 (GCVE-0-2026-63971)

Vulnerability from cvelistv5 – Published: 2026-07-19 14:55 – Updated: 2026-07-20 13:41
VLAI
Title
sctp: fix race between sctp_wait_for_connect and peeloff
Summary
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
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < 0e0d5bc76fd4267a71334fcc8f1a5fbcf997845d (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < bcfeac79af740735ace44008b4a11b8e5add20f5 (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < 8e9b56051d24540cfbf39194618708c4a7633549 (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < 634a9af8a26a84d8b0d7b3b643204b344b42d9fb (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < 7d2038d4b80166f7bead8d07eba3b97405816c21 (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < 68667ee4c7dadf7f63167234e2a1af09b3f7874e (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < 6140cfa721451fa6e18e134e709703c2bf34d0fb (git)
Affected: 668c9beb9020d5834ee9e43c208190a07d2b1928 , < f14fe6395a8b3d961a61e138ad7b36ba3626dd4e (git)
Create a notification for this product.
Linux Linux Affected: 4.16
Unaffected: 0 , < 4.16 (semver)
Unaffected: 5.10.259 , ≤ 5.10.* (semver)
Unaffected: 5.15.210 , ≤ 5.15.* (semver)
Unaffected: 6.1.176 , ≤ 6.1.* (semver)
Unaffected: 6.6.143 , ≤ 6.6.* (semver)
Unaffected: 6.12.93 , ≤ 6.12.* (semver)
Unaffected: 6.18.35 , ≤ 6.18.* (semver)
Unaffected: 7.0.12 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sctp/socket.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0e0d5bc76fd4267a71334fcc8f1a5fbcf997845d",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "bcfeac79af740735ace44008b4a11b8e5add20f5",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "8e9b56051d24540cfbf39194618708c4a7633549",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "634a9af8a26a84d8b0d7b3b643204b344b42d9fb",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "7d2038d4b80166f7bead8d07eba3b97405816c21",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "68667ee4c7dadf7f63167234e2a1af09b3f7874e",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "6140cfa721451fa6e18e134e709703c2bf34d0fb",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            },
            {
              "lessThan": "f14fe6395a8b3d961a61e138ad7b36ba3626dd4e",
              "status": "affected",
              "version": "668c9beb9020d5834ee9e43c208190a07d2b1928",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sctp/socket.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.16"
            },
            {
              "lessThan": "4.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.259",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.210",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.176",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.143",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.93",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.35",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.12",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.259",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.210",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.176",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.143",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.93",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.35",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.12",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "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-\u003ebase.sk. After\nre-acquiring the old socket lock, sctp_wait_for_connect() returns\nsuccess without noticing the migration \u2014 the caller then accesses\nthe association under the wrong lock in sctp_datamsg_from_user().\n\nAdd the same sk != asoc-\u003ebase.sk check that sctp_wait_for_sndbuf()\nalready has, returning an error if the association was migrated while\nwe slept."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-20T13:41:56.086Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/0e0d5bc76fd4267a71334fcc8f1a5fbcf997845d"
        },
        {
          "url": "https://git.kernel.org/stable/c/bcfeac79af740735ace44008b4a11b8e5add20f5"
        },
        {
          "url": "https://git.kernel.org/stable/c/8e9b56051d24540cfbf39194618708c4a7633549"
        },
        {
          "url": "https://git.kernel.org/stable/c/634a9af8a26a84d8b0d7b3b643204b344b42d9fb"
        },
        {
          "url": "https://git.kernel.org/stable/c/7d2038d4b80166f7bead8d07eba3b97405816c21"
        },
        {
          "url": "https://git.kernel.org/stable/c/68667ee4c7dadf7f63167234e2a1af09b3f7874e"
        },
        {
          "url": "https://git.kernel.org/stable/c/6140cfa721451fa6e18e134e709703c2bf34d0fb"
        },
        {
          "url": "https://git.kernel.org/stable/c/f14fe6395a8b3d961a61e138ad7b36ba3626dd4e"
        }
      ],
      "title": "sctp: fix race between sctp_wait_for_connect and peeloff",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-63971",
    "datePublished": "2026-07-19T14:55:57.792Z",
    "dateReserved": "2026-07-19T07:54:57.024Z",
    "dateUpdated": "2026-07-20T13:41:56.086Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-63971",
      "date": "2026-07-21",
      "epss": "0.00164",
      "percentile": "0.06004"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-63971\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-07-19T16:17:16.163\",\"lastModified\":\"2026-07-20T15:16:59.387\",\"vulnStatus\":\"Received\",\"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-\u003ebase.sk. After\\nre-acquiring the old socket lock, sctp_wait_for_connect() returns\\nsuccess without noticing the migration \u2014 the caller then accesses\\nthe association under the wrong lock in sctp_datamsg_from_user().\\n\\nAdd the same sk != asoc-\u003ebase.sk check that sctp_wait_for_sndbuf()\\nalready has, returning an error if the association was migrated while\\nwe slept.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/sctp/socket.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"0e0d5bc76fd4267a71334fcc8f1a5fbcf997845d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"bcfeac79af740735ace44008b4a11b8e5add20f5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"8e9b56051d24540cfbf39194618708c4a7633549\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"634a9af8a26a84d8b0d7b3b643204b344b42d9fb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"7d2038d4b80166f7bead8d07eba3b97405816c21\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"68667ee4c7dadf7f63167234e2a1af09b3f7874e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"6140cfa721451fa6e18e134e709703c2bf34d0fb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"668c9beb9020d5834ee9e43c208190a07d2b1928\",\"lessThan\":\"f14fe6395a8b3d961a61e138ad7b36ba3626dd4e\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/sctp/socket.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"4.16\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"4.16\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.259\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.210\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.176\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.143\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.93\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.35\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0.12\",\"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: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}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0e0d5bc76fd4267a71334fcc8f1a5fbcf997845d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/6140cfa721451fa6e18e134e709703c2bf34d0fb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/634a9af8a26a84d8b0d7b3b643204b344b42d9fb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/68667ee4c7dadf7f63167234e2a1af09b3f7874e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/7d2038d4b80166f7bead8d07eba3b97405816c21\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8e9b56051d24540cfbf39194618708c4a7633549\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/bcfeac79af740735ace44008b4a11b8e5add20f5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/f14fe6395a8b3d961a61e138ad7b36ba3626dd4e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.