CVE-2026-64086
hwmon: (pmbus/adm1266) include PEC byte in pmbus_block_xfer read buffer
Description
In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/adm1266) include PEC byte in pmbus_block_xfer read buffer adm1266_pmbus_block_xfer() sets up the read transaction with .buf = data->read_buf, .len = ADM1266_PMBUS_BLOCK_MAX + 2, but read_buf in struct adm1266_data is declared as u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1]; For a max-length block response (length byte = 255 + up to 1 PEC byte), the i2c controller is told to write 257 bytes into a 256-byte buffer, putting one byte past the end of read_buf. The same response also makes the subsequent PEC compare if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) read a byte beyond the array. Bump the read_buf declaration to ADM1266_PMBUS_BLOCK_MAX + 2 so the buffer can hold the length byte, up to 255 payload bytes, and the PEC byte the i2c_msg length already accounts for.
INFO
Published Date :
July 19, 2026, 4:17 p.m.
Last Modified :
July 19, 2026, 4:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-64086
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Increase read_buf declaration size.
- Ensure buffer can hold length, payload, and PEC byte.
- Apply the provided kernel patch or update.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-64086.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64086 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-64086
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-64086 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64086 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': '397d3f523bfff2f4e3dacf9b1339bd76dc207f78', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': '472744f69d25a2d5111ad62f1d62579dce2c13c8', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': '528a9f88e88502d0c2f2052a279415074cd83715', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': 'd94ceb16e55b6d8019ab069e357c76ac42f0ffbc', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': 'bd5be3fa5de6dbf61f1b3cec6b79c2c2f8065694', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': '2279c342d94eca225bf9f301c8806a05a1c81619', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': 'a6c802145a8de0830bca803c6d415f7e9e683624', 'versionType': 'git'}, {'status': 'affected', 'version': '407dc802a9c0809ca6a48de4b4c63305eb84ef56', 'lessThan': '487566cb1ccdf3756fdd7bf8d875e612ff3169bb', 'versionType': 'git'}], 'programFiles': ['drivers/hwmon/pmbus/adm1266.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.10'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.10', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.258', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.209', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.175', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.142', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/hwmon/pmbus/adm1266.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/adm1266) include PEC byte in pmbus_block_xfer read buffer adm1266_pmbus_block_xfer() sets up the read transaction with .buf = data->read_buf, .len = ADM1266_PMBUS_BLOCK_MAX + 2, but read_buf in struct adm1266_data is declared as u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1]; For a max-length block response (length byte = 255 + up to 1 PEC byte), the i2c controller is told to write 257 bytes into a 256-byte buffer, putting one byte past the end of read_buf. The same response also makes the subsequent PEC compare if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) read a byte beyond the array. Bump the read_buf declaration to ADM1266_PMBUS_BLOCK_MAX + 2 so the buffer can hold the length byte, up to 255 payload bytes, and the PEC byte the i2c_msg length already accounts for. Added Reference https://git.kernel.org/stable/c/2279c342d94eca225bf9f301c8806a05a1c81619 Added Reference https://git.kernel.org/stable/c/397d3f523bfff2f4e3dacf9b1339bd76dc207f78 Added Reference https://git.kernel.org/stable/c/472744f69d25a2d5111ad62f1d62579dce2c13c8 Added Reference https://git.kernel.org/stable/c/487566cb1ccdf3756fdd7bf8d875e612ff3169bb Added Reference https://git.kernel.org/stable/c/528a9f88e88502d0c2f2052a279415074cd83715 Added Reference https://git.kernel.org/stable/c/a6c802145a8de0830bca803c6d415f7e9e683624 Added Reference https://git.kernel.org/stable/c/bd5be3fa5de6dbf61f1b3cec6b79c2c2f8065694 Added Reference https://git.kernel.org/stable/c/d94ceb16e55b6d8019ab069e357c76ac42f0ffbc