{"cve":"CVE-2026-74677","nvd":{"published":"2026-08-22T16:16:41.847","modified":"2026-10-14T13:10:00.187","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: usb: ipheth: fix carrier_work UAF on disconnect\n\nipheth_sndbulk_callback() re-arms the carrier-check work on any\nnon-zero URB status:\n\n\telse\n\t\tschedule_delayed_work(&dev->carrier_work, 0);\n\nNothing ties that to the interface being up, so the work can be armed\nagain after ipheth_close() has already drained it, and stay armed\nuntil the netdev whose private area embeds it is freed.\n\nOn unplug with a TX URB in flight, ipheth_disconnect() drains the work\nthrough unregister_netdev() -> ipheth_close() ->\ncancel_delayed_work_sync() and only then calls ipheth_kill_urbs().\nusb_kill_urb() completes the in-flight TX URB with -ENOENT, so\nipheth_sndbulk_callback() runs after the drain and re-arms\ncarrier_work.\n\nThe same completion also re-arms the work if the interface is only\nbrought down while a TX URB is in flight, and\nipheth_carrier_check_work() then keeps re-queueing itself once a\nsecond. unregister_netdev() does not call ipheth_close() for an\nalready-down interface, so nothing drains it on the later unplug\neither.\n\nIn both cases free_netdev() frees the netdev while carrier_work is\nstill pending, and ipheth_carrier_check_work() dereferences freed\nmemory.\n\nTie the work to the interface state instead of chasing the completion:\ndisable it in ipheth_close() and enable it in ipheth_open(), so a\nschedule_delayed_work() from the URB completion is a no-op whenever\nthe interface is not up. disable_delayed_work_sync() also waits for a\nrunning instance, so it fully replaces the cancel_delayed_work_sync()\nit takes the place of. The work starts out disabled in ipheth_probe()\nso the enable/disable counts balance from the first open.\n\nReproduced under KASAN on linux-next (next-20260731) with dummy_hcd and\nraw-gadget standing in for the device, driving the second path above (the\ninterface is already down, so unregister_netdev() does not call\nipheth_close()): 15 of 15 unpatched boots report a slab-use-after-free in\n__run_timers(), freed by ipheth_disconnect() and re-armed from\nipheth_sndbulk_callback() via queue_delayed_work_on(). The\nsame trigger on a kernel differing only by this patch reports 0 of 15,\nand the carrier check still functions across open/close cycles.\n\nThe reproducer needs an attached USB device that stops draining bulk OUT,\nplus a link down and unplug, driven as root. It is not a privilege\nboundary crossing and no exploit primitive was developed.\n\nFound by 0sec (https://0sec.ai).","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/2c7496124e94c7f9c3daa5c5b1fb563ca9d62c45","https://git.kernel.org/stable/c/48303f3ae0fa6e102f3fc7dbf1688cc179131962","https://git.kernel.org/stable/c/d07133fe1befae9a1e4c4c5e46ef0b73d2992020","https://git.kernel.org/stable/c/fde39b8a521780391fb4e5bda2c0aa4928947f12"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:38.260478770+00:00"},"epss":{"cve":"CVE-2026-74677","score":0.00168,"percentile":0.06036,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}