{"id":"CVE-2025-21877","title":"usbnet: gl620a: fix endpoint checking in genelink_bind()","summary":"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 pr…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 5f2dbabbce04b1ffcd6d8d07564adb94db577536","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 24dd971104057c8828d420a48e0a5af6e6f30d3e","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 9bcb8cbc3e5d67eb223bfb7e2291a270dbb699dc","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 67ebc3391c8377738e97a43374054d9718fdb6e4","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < a2ee5e55b50a97d13617c8653482c0ad4decff8c","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 4e8b8d43373bf837be159366f0192502f97ec7a5","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < ded25730c96949cb8b048b29c557e38569124943","Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 1cf9631d836b289bd5490776551961c883ae8a4f","Linux 2.6.14"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T20:36:10.059834Z"},"published":"2025-03-27","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:41:46.346Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-21877","references":[{"url":"https://git.kernel.org/stable/c/5f2dbabbce04b1ffcd6d8d07564adb94db577536"},{"url":"https://git.kernel.org/stable/c/24dd971104057c8828d420a48e0a5af6e6f30d3e"},{"url":"https://git.kernel.org/stable/c/9bcb8cbc3e5d67eb223bfb7e2291a270dbb699dc"},{"url":"https://git.kernel.org/stable/c/67ebc3391c8377738e97a43374054d9718fdb6e4"},{"url":"https://git.kernel.org/stable/c/a2ee5e55b50a97d13617c8653482c0ad4decff8c"},{"url":"https://git.kernel.org/stable/c/4e8b8d43373bf837be159366f0192502f97ec7a5"},{"url":"https://git.kernel.org/stable/c/ded25730c96949cb8b048b29c557e38569124943"},{"url":"https://git.kernel.org/stable/c/1cf9631d836b289bd5490776551961c883ae8a4f"}],"tags":["cve.org"],"epss":0.00233,"epssPercentile":0.14257,"ingestedAt":"2026-11-05T22:38:31.851Z","slug":"CVE-2025-21877","body":"## Overview\n\nIn 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>\n\n## Affected\n\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 5f2dbabbce04b1ffcd6d8d07564adb94db577536`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 24dd971104057c8828d420a48e0a5af6e6f30d3e`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 9bcb8cbc3e5d67eb223bfb7e2291a270dbb699dc`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 67ebc3391c8377738e97a43374054d9718fdb6e4`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < a2ee5e55b50a97d13617c8653482c0ad4decff8c`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 4e8b8d43373bf837be159366f0192502f97ec7a5`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < ded25730c96949cb8b048b29c557e38569124943`\n- `Linux >= 47ee3051c856cc2aa95d35d577a8cb37279d540f < 1cf9631d836b289bd5490776551961c883ae8a4f`\n- `Linux 2.6.14`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}