{
  "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-2021-47590",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47590",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-06-19T14:53:54.244Z",
    "updatedAt": "2026-05-11T13:57:29.079Z",
    "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": "mptcp: fix deadlock in __mptcp_push_pending()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix deadlock in __mptcp_push_pending()\n\n__mptcp_push_pending() may call mptcp_flush_join_list() with subflow\nsocket lock held. If such call hits mptcp_sockopt_sync_all() then\nsubsequently __mptcp_sockopt_sync() could try to lock the subflow\nsocket for itself, causing a deadlock.\n\nsysrq: Show Blocked State\ntask:ss-server       state:D stack:    0 pid:  938 ppid:     1 flags:0x00000000\nCall Trace:\n <TASK>\n __schedule+0x2d6/0x10c0\n ? __mod_memcg_state+0x4d/0x70\n ? csum_partial+0xd/0x20\n ? _raw_spin_lock_irqsave+0x26/0x50\n schedule+0x4e/0xc0\n __lock_sock+0x69/0x90\n ? do_wait_intr_irq+0xa0/0xa0\n __lock_sock_fast+0x35/0x50\n mptcp_sockopt_sync_all+0x38/0xc0\n __mptcp_push_pending+0x105/0x200\n mptcp_sendmsg+0x466/0x490\n sock_sendmsg+0x57/0x60\n __sys_sendto+0xf0/0x160\n ? do_wait_intr_irq+0xa0/0xa0\n ? fpregs_restore_userregs+0x12/0xd0\n __x64_sys_sendto+0x20/0x30\n do_syscall_64+0x38/0x90\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f9ba546c2d0\nRSP: 002b:00007ffdc3b762d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c\nRAX: ffffffffffffffda RBX: 00007f9ba56c8060 RCX: 00007f9ba546c2d0\nRDX: 000000000000077a RSI: 0000000000e5e180 RDI: 0000000000000234\nRBP: 0000000000cc57f0 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007f9ba56c8060\nR13: 0000000000b6ba60 R14: 0000000000cc7840 R15: 41d8685b1d7901b8\n </TASK>\n\nFix the issue by using __mptcp_flush_join_list() instead of plain\nmptcp_flush_join_list() inside __mptcp_push_pending(), as suggested by\nFlorian. The sockopt sync will be deferred to the workqueue.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "1b3e7ede1365a24db1b4fd837e58a595f52fa4ad",
              "status": "affected",
              "versionType": "git",
              "lessThan": "23311b92755ffa9087332d1bb8c71c0f6a10cc08"
            },
            {
              "version": "1b3e7ede1365a24db1b4fd837e58a595f52fa4ad",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3d79e3756ca90f7a6087b77b62c1d9c0801e0820"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.13",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.13"
            },
            {
              "version": "5.15.11",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.16",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}