{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-05-02T06:55:41.227","vulnerabilities":[{"cve":{"id":"CVE-2022-50220","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2025-06-18T11:15:52.973","lastModified":"2025-11-19T12:59:21.397","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nusbnet: Fix linkwatch use-after-free on disconnect\n\nusbnet uses the work usbnet_deferred_kevent() to perform tasks which may\nsleep.  On disconnect, completion of the work was originally awaited in\n->ndo_stop().  But in 2003, that was moved to ->disconnect() by historic\ncommit \"[PATCH] USB: usbnet, prevent exotic rtnl deadlock\":\n\n  https://git.kernel.org/tglx/history/c/0f138bbfd83c\n\nThe change was made because back then, the kernel's workqueue\nimplementation did not allow waiting for a single work.  One had to wait\nfor completion of *all* work by calling flush_scheduled_work(), and that\ncould deadlock when waiting for usbnet_deferred_kevent() with rtnl_mutex\nheld in ->ndo_stop().\n\nThe commit solved one problem but created another:  It causes a\nuse-after-free in USB Ethernet drivers aqc111.c, asix_devices.c,\nax88179_178a.c, ch9200.c and smsc75xx.c:\n\n* If the drivers receive a link change interrupt immediately before\n  disconnect, they raise EVENT_LINK_RESET in their (non-sleepable)\n  ->status() callback and schedule usbnet_deferred_kevent().\n* usbnet_deferred_kevent() invokes the driver's ->link_reset() callback,\n  which calls netif_carrier_{on,off}().\n* That in turn schedules the work linkwatch_event().\n\nBecause usbnet_deferred_kevent() is awaited after unregister_netdev(),\nnetif_carrier_{on,off}() may operate on an unregistered netdev and\nlinkwatch_event() may run after free_netdev(), causing a use-after-free.\n\nIn 2010, usbnet was changed to only wait for a single instance of\nusbnet_deferred_kevent() instead of *all* work by commit 23f333a2bfaf\n(\"drivers/net: don't use flush_scheduled_work()\").\n\nUnfortunately the commit neglected to move the wait back to\n->ndo_stop().  Rectify that omission at long last."},{"lang":"es","value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: usbnet: Se corrige el Use-After-Free de linkwatch al desconectar. usbnet usa la función usbnet_deferred_kevent() para ejecutar tareas que podrían estar en estado de suspensión. Al desconectar, la finalización de la tarea se esperaba originalmente en ->ndo_stop(). Sin embargo, en 2003, esto se trasladó a ->disconnect() mediante el commit histórica \"[PATCH] USB: usbnet, previene el bloqueo rtnl exótico\": https://git.kernel.org/tglx/history/c/0f138bbfd83c. Este cambio se realizó porque, en aquel entonces, la implementación de la cola de trabajo del kernel no permitía esperar una sola tarea. Se debía esperar la finalización de *todas* las tareas llamando a flush_scheduled_work(), lo que podía provocar un bloqueo al esperar usbnet_deferred_kevent() con rtnl_mutex en ->ndo_stop(). El commit resolvió un problema pero creó otro: Provoca un uso después de la liberación en los controladores Ethernet USB aqc111.c, asix_devices.c, ax88179_178a.c, ch9200.c y smsc75xx.c: * Si los controladores reciben una interrupción de cambio de enlace inmediatamente antes de la desconexión, generan EVENT_LINK_RESET en su devolución de llamada ->status() (no inactiva) y programan usbnet_deferred_kevent(). * usbnet_deferred_kevent() invoca la devolución de llamada ->link_reset() del controlador, que llama a netif_carrier_{on,off}(). * Eso a su vez programa el trabajo linkwatch_event(). Dado que usbnet_deferred_kevent() se espera después de unregister_netdev(), netif_carrier_{on,off}() puede operar en un netdev no registrado y linkwatch_event() puede ejecutarse después de free_netdev(), lo que provoca un error de uso después de la liberación. En 2010, se modificó la configuración de usbnet para que solo esperara una instancia de usbnet_deferred_kevent() en lugar de *todo* el trabajo mediante el commit 23f333a2bfaf (\"drivers/net: no usar flush_scheduled_work()\"). Lamentablemente, el commit no retrasó la espera a ->ndo_stop(). Se corrigió esta omisión de una vez."}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","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}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"CWE-416"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.38","versionEndExcluding":"4.9.326","matchCriteriaId":"4197D395-7363-4526-9658-190ED07AA35D"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"4.14.291","matchCriteriaId":"3BBC7E43-6161-4F21-977C-5BB7792C6C94"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"4.19.256","matchCriteriaId":"6C47CDE3-B039-4AE5-B8E4-1DC820E473FF"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.20","versionEndExcluding":"5.4.211","matchCriteriaId":"B1C63D19-C08C-4308-A848-B2523C9275BD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.137","matchCriteriaId":"C2BF720F-C5EE-4DE2-9BDF-CE4CFBC767F4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.15.61","matchCriteriaId":"51861563-7F40-460F-82CD-2D3FBDAD6618"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"5.18.18","matchCriteriaId":"5B42E453-8837-49D0-A5EF-03F818A6DC11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"5.19.2","matchCriteriaId":"A1A2A5A5-4598-4D7E-BA07-4660398D6C8F"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/135199a2edd459d2b123144efcd7f9bcd95128e4","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/635fd8953e4309b54ca6a81bed1d4a87668694f4","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/7f77dcbc030c2faa6d8e8a594985eeb34018409e","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/8b4588b8b00b299be16a35be67b331d8fdba03f3","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/a69e617e533edddf3fa3123149900f36e0a6dc74","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d2d6b530d89b0a912148018027386aa049f0a309","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d49bb8cf9bfaa06aa527eb30f1a52a071da2e32f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/db3b738ae5f726204876f4303c49cfdf4311403f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/e2a521a7dcc463c5017b4426ca0804e151faeff7","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]}]}}]}