{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-46929",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-46929",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-02-27T09:43:58.047Z",
    "updatedAt": "2026-08-05T08:45:08.476Z",
    "importedAt": "2026-10-24T01:56:36.661Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "sctp: use call_rcu to free endpoint",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: use call_rcu to free endpoint\n\nThis patch is to delay the endpoint free by calling call_rcu() to fix\nanother use-after-free issue in sctp_sock_dump():\n\n  BUG: KASAN: use-after-free in __lock_acquire+0x36d9/0x4c20\n  Call Trace:\n    __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218\n    lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844\n    __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]\n    _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168\n    spin_lock_bh include/linux/spinlock.h:334 [inline]\n    __lock_sock+0x203/0x350 net/core/sock.c:2253\n    lock_sock_nested+0xfe/0x120 net/core/sock.c:2774\n    lock_sock include/net/sock.h:1492 [inline]\n    sctp_sock_dump+0x122/0xb20 net/sctp/diag.c:324\n    sctp_for_each_transport+0x2b5/0x370 net/sctp/socket.c:5091\n    sctp_diag_dump+0x3ac/0x660 net/sctp/diag.c:527\n    __inet_diag_dump+0xa8/0x140 net/ipv4/inet_diag.c:1049\n    inet_diag_dump+0x9b/0x110 net/ipv4/inet_diag.c:1065\n    netlink_dump+0x606/0x1080 net/netlink/af_netlink.c:2244\n    __netlink_dump_start+0x59a/0x7c0 net/netlink/af_netlink.c:2352\n    netlink_dump_start include/linux/netlink.h:216 [inline]\n    inet_diag_handler_cmd+0x2ce/0x3f0 net/ipv4/inet_diag.c:1170\n    __sock_diag_cmd net/core/sock_diag.c:232 [inline]\n    sock_diag_rcv_msg+0x31d/0x410 net/core/sock_diag.c:263\n    netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477\n    sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:274\n\nThis issue occurs when asoc is peeled off and the old sk is freed after\ngetting it by asoc->base.sk and before calling lock_sock(sk).\n\nTo prevent the sk free, as a holder of the sk, ep should be alive when\ncalling lock_sock(). This patch uses call_rcu() and moves sock_put and\nep free into sctp_endpoint_destroy_rcu(), so that it's safe to try to\nhold the ep under rcu_read_lock in sctp_transport_traverse_process().\n\nIf sctp_endpoint_hold() returns true, it means this ep is still alive\nand we have held it and can continue to dump it; If it returns false,\nit means this ep is dead and can be freed after rcu_read_unlock, and\nwe should skip it.\n\nIn sctp_sock_dump(), after locking the sk, if this ep is different from\ntsp->asoc->ep, it means during this dumping, this asoc was peeled off\nbefore calling lock_sock(), and the sk should be skipped; If this ep is\nthe same with tsp->asoc->ep, it means no peeloff happens on this asoc,\nand due to lock_sock, no peeloff will happen either until release_sock.\n\nNote that delaying endpoint free won't delay the port release, as the\nport release happens in sctp_endpoint_destroy() before calling call_rcu().\nAlso, freeing endpoint by call_rcu() makes it safe to access the sk by\nasoc->base.sk in sctp_assocs_seq_show() and sctp_rcv().\n\nThanks Jones to bring this issue up.\n\nv1->v2:\n  - improve the changelog.\n  - add kfree(ep) into sctp_endpoint_destroy_rcu(), as Jakub noticed.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8873140f95d4977bf37e4cf0d5c5e3f6e34cdd3e"
            },
            {
              "version": "d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "af6e6e58f7ebf86b4e7201694b1e4f3a62cbc3ec"
            },
            {
              "version": "d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "831de271452b87657fcf8d715ee20519b79caef5"
            },
            {
              "version": "d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "769d14abd35e0e153b5149c3e1e989a9d719e3ff"
            },
            {
              "version": "d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "75799e71df1da11394740b43ae5686646179561d"
            },
            {
              "version": "d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5ec7d18d1813a5bead0b495045606c93873aecbb"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.14",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.14"
            },
            {
              "version": "4.14.261",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "4.14.*"
            },
            {
              "version": "4.19.224",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "version": "5.4.170",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "version": "5.10.90",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.13",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.16",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}