{"id":"CVE-2026-53194","revision":"432f8b81e5ea48bbad199e9c3f62cf02","records":[{"revision":"432f8b81e5ea48bbad199e9c3f62cf02","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-53194","aliases":[],"title":"USB: serial: kl5kusb105: fix bulk-out buffer overflow","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: kl5kusb105: fix bulk-out buffer overflow\n\nklsi_105_prepare_write_buffer() is called by the generic write path\nwith the bulk-out buffer and its size (bulk_out_size, 64 bytes). It\nstores a two-byte length header at the start of the buffer and copies\nthe payload from the write fifo starting at buf + KLSI_HDR_LEN, but\npasses the full buffer size as the number of bytes to copy:\n\n  count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN,\n                           size, &port->lock);\n\nWhen the fifo holds at least size bytes, size bytes are copied starting\ntwo bytes into the size-byte buffer, writing KLSI_HDR_LEN bytes past its\nend. Copy at most size - KLSI_HDR_LEN bytes instead, leaving room for\nthe header as safe_serial already does.\n\nWriting bulk_out_size or more bytes to the tty triggers a slab\nout-of-bounds write, observed with KASAN by emulating the device with\ndummy_hcd and raw-gadget:\n\n  BUG: KASAN: slab-out-of-bounds in kfifo_copy_out+0x83/0xc0\n  Write of size 64 at addr ffff888112c62202 by task python3\n   kfifo_copy_out\n   klsi_105_prepare_write_buffer [kl5kusb105]\n   usb_serial_generic_write_start [usbserial]\n  Allocated by task 139:\n   usb_serial_probe [usbserial]\n  The buggy address is located 2 bytes inside of allocated 64-byte region\n\nThe out-of-bounds write no longer occurs with this change applied.","state":0,"publishedAt":"2026-06-25T08:39:05.017+00:00","modifiedAt":"2026-10-19T19:57:28.103+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/usb/serial/kl5kusb105.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"60af1fd82983c26604102e63a3fcc822c186cceb\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"0a57320f71941d4e0b1307453c9a1f0939afe666\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"14147b7963685957839c76ba8094924e22777d79\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"a1288cd700f721c1a119c4f1e8efa234e59caada\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"70d86e355c564b5510fde61361df014f5476c83e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"372f33ebed747d91870f57c0a2e62884a870bffa\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"bde742b076cbe26ecc89c8c68c76ae076a524d02\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"60b3013cdaf3fa8a17243ca46b19db3cbe08d943\",\n                            \"lessThan\": \"96d47e40bf9db4a9efd5c8fb53287a508d165f14\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/usb/serial/kl5kusb105.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.35\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.35\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.259\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.210\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.176\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.143\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.94\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.36\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.13\",\n                            \"lessThanOrEqual\": \"7.0.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 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,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/60af1fd82983c26604102e63a3fcc822c186cceb","https://git.kernel.org/stable/c/0a57320f71941d4e0b1307453c9a1f0939afe666","https://git.kernel.org/stable/c/14147b7963685957839c76ba8094924e22777d79","https://git.kernel.org/stable/c/a1288cd700f721c1a119c4f1e8efa234e59caada","https://git.kernel.org/stable/c/70d86e355c564b5510fde61361df014f5476c83e","https://git.kernel.org/stable/c/372f33ebed747d91870f57c0a2e62884a870bffa","https://git.kernel.org/stable/c/bde742b076cbe26ecc89c8c68c76ae076a524d02","https://git.kernel.org/stable/c/96d47e40bf9db4a9efd5c8fb53287a508d165f14"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53194","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-53194","identifiers":["CVE-2026-53194"]},"retained":false,"historicalAffected":[]}],"coverage":[]}