{"id":"CVE-2026-64086","summary":"hwmon: (pmbus/adm1266) include PEC byte in pmbus_block_xfer read buffer","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/adm1266) include PEC byte in pmbus_block_xfer read buffer\n\nadm1266_pmbus_block_xfer() sets up the read transaction with\n\n\t.buf = data-\u003eread_buf,\n\t.len = ADM1266_PMBUS_BLOCK_MAX + 2,\n\nbut read_buf in struct adm1266_data is declared as\n\n\tu8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1];\n\nFor a max-length block response (length byte = 255 + up to 1 PEC\nbyte), the i2c controller is told to write 257 bytes into a 256-byte\nbuffer, putting one byte past the end of read_buf.  The same response\nalso makes the subsequent PEC compare\n\n\tif (crc != msgs[1].buf[msgs[1].buf[0] + 1])\n\nread a byte beyond the array.\n\nBump the read_buf declaration to ADM1266_PMBUS_BLOCK_MAX + 2 so the\nbuffer can hold the length byte, up to 255 payload bytes, and the PEC\nbyte the i2c_msg length already accounts for.","modified":"2026-07-22T05:29:45.912554466Z","published":"2026-07-19T15:39:56.749Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64086.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2279c342d94eca225bf9f301c8806a05a1c81619"},{"type":"WEB","url":"https://git.kernel.org/stable/c/397d3f523bfff2f4e3dacf9b1339bd76dc207f78"},{"type":"WEB","url":"https://git.kernel.org/stable/c/472744f69d25a2d5111ad62f1d62579dce2c13c8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/487566cb1ccdf3756fdd7bf8d875e612ff3169bb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/528a9f88e88502d0c2f2052a279415074cd83715"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a6c802145a8de0830bca803c6d415f7e9e683624"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bd5be3fa5de6dbf61f1b3cec6b79c2c2f8065694"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d94ceb16e55b6d8019ab069e357c76ac42f0ffbc"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64086.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64086"},{"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":"407dc802a9c0809ca6a48de4b4c63305eb84ef56"},{"fixed":"397d3f523bfff2f4e3dacf9b1339bd76dc207f78"},{"fixed":"472744f69d25a2d5111ad62f1d62579dce2c13c8"},{"fixed":"528a9f88e88502d0c2f2052a279415074cd83715"},{"fixed":"d94ceb16e55b6d8019ab069e357c76ac42f0ffbc"},{"fixed":"bd5be3fa5de6dbf61f1b3cec6b79c2c2f8065694"},{"fixed":"2279c342d94eca225bf9f301c8806a05a1c81619"},{"fixed":"a6c802145a8de0830bca803c6d415f7e9e683624"},{"fixed":"487566cb1ccdf3756fdd7bf8d875e612ff3169bb"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64086.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.10.0"},{"fixed":"5.10.258"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.209"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.175"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.142"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.92"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.34"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64086.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}