{"cve":"CVE-2026-64424","nvd":{"published":"2026-07-25T10:17:26.483","modified":"2026-10-30T13:19:36.340","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetpoll: fix a use-after-free on shutdown path\n\nThere is a use-after-free error on netpoll, which is clearly detected by\nKASAN.\n\n      BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x3b/0x80\n      Read of size 1 at addr ... by task kworker/9:1\n      Workqueue: events queue_process\n      Call Trace:\n       skb_dequeue+0x1e/0xb0\n       queue_process+0x2c/0x600\n       process_scheduled_works+0x4b6/0x850\n       worker_thread+0x414/0x5a0\n      Allocated by task 242:\n       __netpoll_setup+0x201/0x4a0\n       netpoll_setup+0x249/0x550\n       enabled_store+0x32f/0x380\n      Freed by task 0:\n       kfree+0x1b7/0x540\n       rcu_core+0x3f8/0x7a0\n\nThe problem happens when there is a pending TX worker running in\nparallel with the cleanup path.\n\nThis is what happens on netpoll shutdown path:\n\n1) __netpoll_cleanup() is called\n2) set dev->npinfo to NULL\n3) call_rcu() with rcu_cleanup_netpoll_info()\n  3.1) rcu_cleanup_netpoll_info() tries to cancel all workers with\n       cancel_delayed_work(), but doesn't wait for the worker to finish\n4) and kfree(npinfo);\n\nBecause 3.1) doesn't really cancel the work, as the comment says \"we\ncan't call cancel_delayed_work_sync here, as we are in softirq\", the TX\nworker can run after 4).\n\nTl;DR: queue_process() is not an RCU reader, it reaches npinfo through\nthe work item via container_of().\n\nUse disable_delayed_work_sync() to ensure the worker is completely\nstopped and prevent any future re-arming attempts. Once npinfo is set\nto NULL, senders will bail out and not queue new work. The disable flag\nensures any in-flight re-arming attempts also fail silently.\n\nIn the future, we can do the cleanup inline here without needing the\nnpinfo->rcu rcu_head, but that is net-next material.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/45f1458a85017a023f138b22ac5c76abd477db42","https://git.kernel.org/stable/c/5ed09a108d93a3b002cc79823d9455b50c4a8be7","https://git.kernel.org/stable/c/95ecc5b58042f6b6743b589e6588f1cd7ba336aa","https://git.kernel.org/stable/c/a33f37f8d079da7236ed7b7e2aed2a34ab81e7cf","https://git.kernel.org/stable/c/b67625b85c4b1a3725f4be9c6dd8ce3399d11732"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-30T13:47:47.119061695+00:00"},"epss":{"cve":"CVE-2026-64424","score":0.00125,"percentile":0.02191,"date":"2026-10-30"},"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."]}