{"id":"CVE-2025-71079","url":"https://www.cyber-defence.io/tools/cve/CVE-2025-71079","generatedAt":"2026-10-27T23:08:19.126Z","title":"In the Linux kernel, the following vulnerability has been resolved: net: nfc: fix deadlock between nfc_unregister_device and rfkill_fop_write A deadlock can occur between nfc_unregister_device() and rfkill_fop_write() due to lock ordering inversion…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: nfc: fix deadlock between nfc_unregister_device and rfkill_fop_write\n\nA deadlock can occur between nfc_unregister_device() and rfkill_fop_write()\ndue to lock ordering inversion between device_lock and rfkill_global_mutex.\n\nThe problematic lock order is:\n\nThread A (rfkill_fop_write):\n  rfkill_fop_write()\n    mutex_lock(&rfkill_global_mutex)\n      rfkill_set_block()\n        nfc_rfkill_set_block()\n          nfc_dev_down()\n            device_lock(&dev->dev)    <- waits for device_lock\n\nThread B (nfc_unregister_device):\n  nfc_unregister_device()\n    device_lock(&dev->dev)\n      rfkill_unregister()\n        mutex_lock(&rfkill_global_mutex)  <- waits for rfkill_global_mutex\n\nThis creates a classic ABBA deadlock scenario.\n\nFix this by moving rfkill_unregister() and rfkill_destroy() outside the\ndevice_lock critical section. Store the rfkill pointer in a local variable\nbefore releasing the lock, then call rfkill_unregister() after releasing\ndevice_lock.\n\nThis change is safe because rfkill_fop_write() holds rfkill_global_mutex\nwhile calling the rfkill callbacks, and rfkill_unregister() also acquires\nrfkill_global_mutex before cleanup. Therefore, rfkill_unregister() will\nwait for any ongoing callback to complete before proceeding, and\ndevice_del() is only called after rfkill_unregister() returns, preventing\nany use-after-free.\n\nThe similar lock ordering in nfc_register_device() (device_lock ->\nrfkill_global_mutex via rfkill_register) is safe because during\nregistration the device is not yet in rfkill_list, so no concurrent\nrfkill operations can occur on this device.","published":"2026-01-13T16:16:07.000Z","lastModified":"2026-10-15T02:18:17.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-667"],"affected":["linux/linux kernel"],"epss":{"score":0.00106,"percentile":0.01115,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.11%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/1ab526d97a57e44d26fadcc0e9adeb9c0c0182f5","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2e0831e9fc46a06daa6d4d8d57a2738e343130c3","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6b93c8ab6f6cda8818983a4ae3fcf84b023037b4","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8fc4632fb508432895430cd02b38086bdd649083","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e02a1c33f10a0ed3aba855ab8ae2b6c4c5be8012","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ee41f4f3ccf8cd6ba3732e867abbec7e6d8d12e5","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f3a8a7c1aa278f2378b2f3a10500c6674dffdfda","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-71079","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}