{"id":"CVE-2026-80827","summary":"USB: serial: option: fix slab OOB read in interrupt URB callback","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: option: fix slab OOB read in interrupt URB callback\n\nThe interrupt URB buffer is allocated in setup_port_interrupt_in() based\non the endpoint's wMaxPacketSize:\n\n    buffer_size = usb_endpoint_maxp(epd);\n    port-\u003einterrupt_in_buffer = kmalloc(buffer_size, GFP_KERNEL);\n\nWhen a USB device declares wMaxPacketSize = 8 on its interrupt IN\nendpoint, the buffer is allocated from kmalloc-8 cache (exactly\n8 bytes).\n\nIf the device sends a short packet (actual_length \u003c wMaxPacketSize),\nthe URB completes with status == 0 and the callback proceeds to read:\n\n    data[sizeof(struct usb_ctrlrequest)]\n\nwhich evaluates to data[8], accessing 1 byte beyond the allocated 8-byte\nbuffer. This results in a slab out-of-bounds read.\n\nFix this by adding the missing bounds check: first verify that the\nactual length is large enough to contain the struct usb_ctrlrequest\nheader before accessing req_pkt-\u003ebRequestType and req_pkt-\u003ebRequest,\nand then verify that there is an additional byte for the modem signal\nstate before reading data[sizeof(struct usb_ctrlrequest)] inside the\nconditional.  Use sizeof(*req_pkt) instead of sizeof(struct\nusb_ctrlrequest) for consistency.\n\n[ johan: use dev_err(); split signals declaration and initialisation ]","modified":"2026-09-06T03:46:48.584741662Z","published":"2026-09-04T15:54:31.111Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80827.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/030e3a73d3c3aa67c44454649e984d6383cdb7d3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/060db7d48af1e650643c8b8319111a9ea2ce4486"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2ef5560387f2c0713cee975be2b24b281bd90f3e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6b8cf5422c7e96ed5b22a8368eff663f3f98b8ec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/885d802f544ca7bfa8f3984d94233cce715bb6b3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/94e5525697b9e91ddc4071129874120a50a4f342"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a72a13c83a652516a0e469d275b81d29a7429049"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d762aef4eba354066be21a5d88eb2066e282f4c9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fbe60fd2abc8a5561f39719a41ad9a01b5d8e567"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80827.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80827"},{"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":"58cfe9113e485f7e04bd0eac4fc4251b330af501"},{"fixed":"fbe60fd2abc8a5561f39719a41ad9a01b5d8e567"},{"fixed":"94e5525697b9e91ddc4071129874120a50a4f342"},{"fixed":"6b8cf5422c7e96ed5b22a8368eff663f3f98b8ec"},{"fixed":"030e3a73d3c3aa67c44454649e984d6383cdb7d3"},{"fixed":"060db7d48af1e650643c8b8319111a9ea2ce4486"},{"fixed":"2ef5560387f2c0713cee975be2b24b281bd90f3e"},{"fixed":"a72a13c83a652516a0e469d275b81d29a7429049"},{"fixed":"d762aef4eba354066be21a5d88eb2066e282f4c9"},{"fixed":"885d802f544ca7bfa8f3984d94233cce715bb6b3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80827.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.12"},{"fixed":"5.10.269"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.220"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.187"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.156"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.108"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.49"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.13"}]},{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.2.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80827.json"}}],"schema_version":"1.9.0"}