CVE-2026-64135

Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/adm1266) widen blackbox-info buffer to I2C_SMBUS_BLOCK_MAX adm1266_nvmem_read_blackbox() declares a 5-byte stack buffer and passes it to i2c_smbus_read_block_data() to retrieve the 4-byte BLACKBOX_INFO response. i2c_smbus_read_block_data() does not honour caller buffer sizes -- it memcpy()s data.block[0] bytes from the SMBus transaction (where data.block[0] is the length byte returned by the slave device, up to I2C_SMBUS_BLOCK_MAX = 32): memcpy(values, &data.block[1], data.block[0]); If the device returns any block length above 5, the call overflows the caller's 5-byte stack buffer before the post-call if (ret != 4) return -EIO; check has a chance to reject the response. Widen the local buffer to I2C_SMBUS_BLOCK_MAX so the helper has room for any well-formed SMBus block response, matching the convention used by the other i2c_smbus_read_block_data() callers in this driver.

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EPSS — Exploit Prediction

0.0018

Probability of exploitation

0.07%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/0dbf64c502443c08c2e28a77ecbfcc5479d93228 https://git.kernel.org/stable/c/2b7a698d5093b548c464828d984f05ced5f3fd2a https://git.kernel.org/stable/c/33251abb9c9dd62943be76f0427c5527ee39188f https://git.kernel.org/stable/c/6ed16a40b162e9d87d9ac8bed4d7f0e3e807700e https://git.kernel.org/stable/c/7f705e581ef3e6bb308a121a89adf5237d968204 https://git.kernel.org/stable/c/ba09f4baa5bd96c5d26c942defa546a72dbbe5bf https://git.kernel.org/stable/c/ca560f7566df7e2826c2999e959e6b94eb938f76 https://git.kernel.org/stable/c/eee213daa1e1b402eb631bcd1b8c5aa340a6b081

Frequently Asked Questions

What is CVE-2026-64135? +

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/adm1266) widen blackbox-info buffer to I2C_SMBUS_BLOCK_MAX adm1266_nvmem_read_blackbox() declares a 5-byte stack buffer and passes it to i2c_smbus_read_block_data() to retrieve the 4-byte BLACKBOX_INFO response. i2c_smbus_read_block_data() does not honour caller buffer sizes -- it memcpy()s data.block[0] bytes from the SMBus transaction (where data.block[0] is the length byte returned by the slave device, up to I2C_SMBUS_BLOCK_MAX = 32): memcpy(values, &data.block[1], data.block[0]); If the device returns any block length above 5, the call overflows the caller's 5-byte stack buffer before the post-call if (ret != 4) return -EIO; check has a chance to reject the response. Widen the local buffer to I2C_SMBUS_BLOCK_MAX so the helper has room for any well-formed SMBus block response, matching the convention used by the other i2c_smbus_read_block_data() callers in this driver.

How do I check if I'm vulnerable to CVE-2026-64135? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.