{"id":"CVE-2026-98771","summary":"usb: storage: sierra_ms: reject short SWoC info transfers","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: storage: sierra_ms: reject short SWoC info transfers\n\nsierra_get_swoc_info() requests sizeof(struct swoc_info) (60) bytes\nfrom the device via usb_control_msg(), but its callers only treat a\nnegative return value as failure. A device that answers the\nvendor-specific GetSwocInfo request with a short IN transfer is\ntherefore accepted, leaving the tail of the freshly allocated\n(kmalloc(), non-zeroing) swoc_info buffer uninitialized.\n\ntruinst_show() subsequently prints swocInfo-\u003erev, swocInfo-\u003eLinuxSKU\nand swocInfo-\u003eLinuxVer from that buffer into the world-readable\n(0444) \"truinst\" sysfs attribute. An emulated/malicious USB device\n(VID 0x1199, PID 0x0fff) can exploit this to disclose up to 5 bytes\nof stale kernel heap memory (kmalloc-64) to unprivileged userspace,\nonce per sysfs read, indefinitely. On kernels built without\ninit_on_alloc this leaks recently freed heap contents.\n\nOnly accept the transfer when the full structure was received.\nsierra_ms_init() already retries failed queries, so well-behaved\ndevices are unaffected.","modified":"2026-10-20T02:30:25.029274769Z","published":"2026-10-18T15:48:07.367Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98771.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8a0200d14acd9db388b85cd016e68a4e60d900ec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c85e8331d298b8f1dee8fe63718e76435cec7133"},{"type":"WEB","url":"https://git.kernel.org/stable/c/db9d3be156baca6ef80ae5d93acfeb85c61a74dd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e2d62928f2666a2964a23b1d39e6e762f0628d7b"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98771.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98771"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"32fe5e393455d87db4988af03915634304870fb4"},{"fixed":"c85e8331d298b8f1dee8fe63718e76435cec7133"},{"fixed":"e2d62928f2666a2964a23b1d39e6e762f0628d7b"},{"fixed":"db9d3be156baca6ef80ae5d93acfeb85c61a74dd"},{"fixed":"8a0200d14acd9db388b85cd016e68a4e60d900ec"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98771.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.27"},{"fixed":"6.12.113"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.56"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98771.json"}}],"schema_version":"1.9.0"}