{"cve":"CVE-2025-21877","nvd":{"published":"2025-03-27T15:15:55.540","modified":"2026-06-17T08:44:30.733","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nusbnet: gl620a: fix endpoint checking in genelink_bind()\n\nSyzbot reports [1] a warning in usb_submit_urb() triggered by\ninconsistencies between expected and actually present endpoints\nin gl620a driver. Since genelink_bind() does not properly\nverify whether specified eps are in fact provided by the device,\nin this case, an artificially manufactured one, one may get a\nmismatch.\n\nFix the issue by resorting to a usbnet utility function\nusbnet_get_endpoints(), usually reserved for this very problem.\nCheck for endpoints and return early before proceeding further if\nany are missing.\n\n[1] Syzbot report:\nusb 5-1: Manufacturer: syz\nusb 5-1: SerialNumber: syz\nusb 5-1: config 0 descriptor??\ngl620a 5-1:0.23 usb0: register 'gl620a' at usb-dummy_hcd.0-1, ...\n------------[ cut here ]------------\nusb 5-1: BOGUS urb xfer, pipe 3 != type 1\nWARNING: CPU: 2 PID: 1841 at drivers/usb/core/urb.c:503 usb_submit_urb+0xe4b/0x1730 drivers/usb/core/urb.c:503\nModules linked in:\nCPU: 2 UID: 0 PID: 1841 Comm: kworker/2:2 Not tainted 6.12.0-syzkaller-07834-g06afb0f36106 #0\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014\nWorkqueue: mld mld_ifc_work\nRIP: 0010:usb_submit_urb+0xe4b/0x1730 drivers/usb/core/urb.c:503\n...\nCall Trace:\n <TASK>\n usbnet_start_xmit+0x6be/0x2780 drivers/net/usb/usbnet.c:1467\n __netdev_start_xmit include/linux/netdevice.h:5002 [inline]\n netdev_start_xmit include/linux/netdevice.h:5011 [inline]\n xmit_one net/core/dev.c:3590 [inline]\n dev_hard_start_xmit+0x9a/0x7b0 net/core/dev.c:3606\n sch_direct_xmit+0x1ae/0xc30 net/sched/sch_generic.c:343\n __dev_xmit_skb net/core/dev.c:3827 [inline]\n __dev_queue_xmit+0x13d4/0x43e0 net/core/dev.c:4400\n dev_queue_xmit include/linux/netdevice.h:3168 [inline]\n neigh_resolve_output net/core/neighbour.c:1514 [inline]\n neigh_resolve_output+0x5bc/0x950 net/core/neighbour.c:1494\n neigh_output include/net/neighbour.h:539 [inline]\n ip6_finish_output2+0xb1b/0x2070 net/ipv6/ip6_output.c:141\n __ip6_finish_output net/ipv6/ip6_output.c:215 [inline]\n ip6_finish_output+0x3f9/0x1360 net/ipv6/ip6_output.c:226\n NF_HOOK_COND include/linux/netfilter.h:303 [inline]\n ip6_output+0x1f8/0x540 net/ipv6/ip6_output.c:247\n dst_output include/net/dst.h:450 [inline]\n NF_HOOK include/linux/netfilter.h:314 [inline]\n NF_HOOK include/linux/netfilter.h:308 [inline]\n mld_sendpack+0x9f0/0x11d0 net/ipv6/mcast.c:1819\n mld_send_cr net/ipv6/mcast.c:2120 [inline]\n mld_ifc_work+0x740/0xca0 net/ipv6/mcast.c:2651\n process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229\n process_scheduled_works kernel/workqueue.c:3310 [inline]\n worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391\n kthread+0x2c1/0x3a0 kernel/kthread.c:389\n ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\n </TASK>","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/1cf9631d836b289bd5490776551961c883ae8a4f","https://git.kernel.org/stable/c/24dd971104057c8828d420a48e0a5af6e6f30d3e","https://git.kernel.org/stable/c/4e8b8d43373bf837be159366f0192502f97ec7a5","https://git.kernel.org/stable/c/5f2dbabbce04b1ffcd6d8d07564adb94db577536","https://git.kernel.org/stable/c/67ebc3391c8377738e97a43374054d9718fdb6e4"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:00:28.034033815+00:00"},"epss":{"cve":"CVE-2025-21877","score":0.00218,"percentile":0.12346,"date":"2026-10-31"},"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."]}