{
  "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-2021-47271",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47271",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-21T14:20:00.703Z",
    "updatedAt": "2026-05-11T13:51:16.818Z",
    "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": "usb: cdnsp: Fix deadlock issue in cdnsp_thread_irq_handler",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: cdnsp: Fix deadlock issue in cdnsp_thread_irq_handler\n\nPatch fixes the following critical issue caused by deadlock which has been\ndetected during testing NCM class:\n\nsmp: csd: Detected non-responsive CSD lock (#1) on CPU#0\nsmp:     csd: CSD lock (#1) unresponsive.\n....\nRIP: 0010:native_queued_spin_lock_slowpath+0x61/0x1d0\nRSP: 0018:ffffbc494011cde0 EFLAGS: 00000002\nRAX: 0000000000000101 RBX: ffff9ee8116b4a68 RCX: 0000000000000000\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9ee8116b4658\nRBP: ffffbc494011cde0 R08: 0000000000000001 R09: 0000000000000000\nR10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658\nR13: ffff9ee8116b4670 R14: 0000000000000246 R15: ffff9ee8116b4658\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f7bcc41a830 CR3: 000000007a612003 CR4: 00000000001706e0\nCall Trace:\n <IRQ>\n do_raw_spin_lock+0xc0/0xd0\n _raw_spin_lock_irqsave+0x95/0xa0\n cdnsp_gadget_ep_queue.cold+0x88/0x107 [cdnsp_udc_pci]\n usb_ep_queue+0x35/0x110\n eth_start_xmit+0x220/0x3d0 [u_ether]\n ncm_tx_timeout+0x34/0x40 [usb_f_ncm]\n ? ncm_free_inst+0x50/0x50 [usb_f_ncm]\n __hrtimer_run_queues+0xac/0x440\n hrtimer_run_softirq+0x8c/0xb0\n __do_softirq+0xcf/0x428\n asm_call_irq_on_stack+0x12/0x20\n </IRQ>\n do_softirq_own_stack+0x61/0x70\n irq_exit_rcu+0xc1/0xd0\n sysvec_apic_timer_interrupt+0x52/0xb0\n asm_sysvec_apic_timer_interrupt+0x12/0x20\nRIP: 0010:do_raw_spin_trylock+0x18/0x40\nRSP: 0018:ffffbc494138bda8 EFLAGS: 00000246\nRAX: 0000000000000000 RBX: ffff9ee8116b4658 RCX: 0000000000000000\nRDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9ee8116b4658\nRBP: ffffbc494138bda8 R08: 0000000000000001 R09: 0000000000000000\nR10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658\nR13: ffff9ee8116b4670 R14: ffff9ee7b5c73d80 R15: ffff9ee8116b4000\n _raw_spin_lock+0x3d/0x70\n ? cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci]\n cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci]\n ? cdnsp_remove_request+0x1f0/0x1f0 [cdnsp_udc_pci]\n ? cdnsp_thread_irq_handler+0x5/0xa0 [cdnsp_udc_pci]\n ? irq_thread+0xa0/0x1c0\n irq_thread_fn+0x28/0x60\n irq_thread+0x105/0x1c0\n ? __kthread_parkme+0x42/0x90\n ? irq_forced_thread_fn+0x90/0x90\n ? wake_threads_waitq+0x30/0x30\n ? irq_thread_check_affinity+0xe0/0xe0\n kthread+0x12a/0x160\n ? kthread_park+0x90/0x90\n ret_from_fork+0x22/0x30\n\nThe root cause of issue is spin_lock/spin_unlock instruction instead\nspin_lock_irqsave/spin_lock_irqrestore in cdnsp_thread_irq_handler\nfunction.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "3d82904559f4f5a2622db1b21de3edf2eded7664",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ae746b6f4ce619cf4032fd798a232b010907a397"
            },
            {
              "version": "3d82904559f4f5a2622db1b21de3edf2eded7664",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a9aecef198faae3240921b707bc09b602e966fce"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.12",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.12"
            },
            {
              "version": "5.12.11",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.12.*"
            },
            {
              "version": "5.13",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}