{"id":"CVE-2026-64331","summary":"usbip: vudc: fix NULL deref in vep_dequeue()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nusbip: vudc: fix NULL deref in vep_dequeue()\n\nvep_alloc_request() wasn't initializing vrequest-\u003eudc, so cancellations\non the FunctionFS AIO path were arriving in vep_dequeue without a valid\nUDC reference.\n\nSince vrequest-\u003eudc is never actually properly used anywhere, we opt to\nremove it, and update vep_dequeue to obtain a reference to the udc with\nep_to_vudc(), consistent with the other vep_ ops.\n\nAFAICT this bug has existed for ~10 years. Seems that nobody has really\nstressed the FunctionFS AIO path on usbip's vudc.\n\nI tested this fix in a QEMU aarch64 guest driving FunctionFS endpoints\nvia AIO. Before the fix, running `usbip attach` from the host would\ncause the guest to oops with the following backtrace:\n\nCall trace:\n vep_dequeue+0x1c/0xe4 (P)\n usb_ep_dequeue+0x14/0x20\n ffs_aio_cancel+0x24/0x34\n __arm64_sys_io_cancel+0xb0/0x124\n do_el0_svc+0x68/0x100\n el0_svc+0x18/0x5c\n el0t_64_sync_handler+0x98/0xdc\n el0t_64_sync+0x154/0x158","modified":"2026-07-27T04:03:21.484276156Z","published":"2026-07-25T08:49:58.370Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64331.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0025276175fbbe0dcbf3f84d090b0adee769e9d9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0443e4416aa1ee97748d1ed904eaf3352c60045e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1226293ec9bed3d4cc5b05eeeb811d315ca51652"},{"type":"WEB","url":"https://git.kernel.org/stable/c/347b59e9f96719d89b6ef555d02a18ada1a5846f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3750f75f29f99c0223601e2ee73ad084adec47bd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9858c91d9ee6a13c45311569039413729fc9b757"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c5371e0b91b24159a3ebaa61e70b0980bcf03c0a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64331.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64331"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"b6a0ca11186759ad7045d68a5447b1e89f658384"},{"fixed":"9858c91d9ee6a13c45311569039413729fc9b757"},{"fixed":"1226293ec9bed3d4cc5b05eeeb811d315ca51652"},{"fixed":"3750f75f29f99c0223601e2ee73ad084adec47bd"},{"fixed":"d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97"},{"fixed":"0025276175fbbe0dcbf3f84d090b0adee769e9d9"},{"fixed":"347b59e9f96719d89b6ef555d02a18ada1a5846f"},{"fixed":"0443e4416aa1ee97748d1ed904eaf3352c60045e"},{"fixed":"c5371e0b91b24159a3ebaa61e70b0980bcf03c0a"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64331.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.7.0"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64331.json"}}],"schema_version":"1.7.5"}