{"id":"CVE-2026-89621","summary":"HID: mcp2221: validate report size in mcp2221_raw_event()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: mcp2221: validate report size in mcp2221_raw_event()\n\nmcp2221_raw_event() never validates the size of incoming HID reports.\nIn the MCP2221_I2C_GET_DATA path it trusts the device-supplied data[3]\nas the copy length without checking that 4 + data[3] bytes actually\nexist in the received report. A malicious or misbehaving USB device can\nsend a short report with a large data[3], causing the memcpy to read\npast the valid report data in the HID transfer buffer and leak\nuninitialized kernel memory back to userspace through the I2C/SMBus\nread path.\n\nAdd a minimum size check at entry and validate that the source range\nfits within the received report before the copy.","modified":"2026-09-13T03:47:19.721872187Z","published":"2026-09-11T19:45:19.420Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89621.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/127de5919820f88a9d55e8371ad4ac49f625f4c5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2c9a6998c19503626c57a2267bf279e204113079"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7c18fb36708a97ff6772825cc087b6d537bbf0d5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bdc6a3af0dd734a326acdb7d6401a3b6a9f4f149"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89621.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89621"},{"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":"67a95c21463d066060b0f66d65a75d45bb386ffb"},{"fixed":"bdc6a3af0dd734a326acdb7d6401a3b6a9f4f149"},{"fixed":"127de5919820f88a9d55e8371ad4ac49f625f4c5"},{"fixed":"7c18fb36708a97ff6772825cc087b6d537bbf0d5"},{"fixed":"2c9a6998c19503626c57a2267bf279e204113079"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89621.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.7.0"},{"fixed":"6.12.109"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.50"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89621.json"}}],"schema_version":"1.9.0"}