CVE-2026-46001

CVE-2026-46001 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pt5161l) Fix bugs in pt5161l_read_block_data() Fix two bugs in pt5161l_read_block_data(): 1. Buffer overrun: The local buffer rbuf is declared as u8 rbuf[24], but i2c_smbus_read_block_data() can return up to I2C_SMBUS_BLOCK_MAX (32) bytes. The i2c-core copies the data into the caller's buffer before the return value can be checked, so the post-read length validation does not prevent a stack overrun if a device returns more than 24 bytes. Resize the buffer to I2C_SMBUS_BLOCK_MAX. 2. Unexpected positive return on length mismatch: When all three retries are exhausted because the device returns data with an unexpected length, i2c_smbus_read_block_data() returns a positive byte count. The function returns this directly, and callers treat any non-negative return as success, processing stale or incomplete buffer contents. Return -EIO when retries are exhausted with a positive return value, preserving the negative error code on I2C failure.

Frequently asked questions

What is CVE-2026-46001?
In the Linux kernel, the following vulnerability has been resolved: hwmon: (pt5161l) Fix bugs in pt5161l_read_block_data() Fix two bugs in pt5161l_read_block_data(): 1. Buffer overrun: The local buffer rbuf is declared as u8 rbuf[24], but i2c_smbus_read_block_data() can return up to I2C_SMBUS_BLOCK_MAX (32) bytes. The i2c-core copies the data into the caller's buffer before the return value can be checked, so the post-read length validation does not prevent a stack overrun if a device returns more than 24 bytes. Resize the buffer to I2C_SMBUS_BLOCK_MAX. 2. Unexpected positive return on length mismatch: When all three retries are exhausted because the device returns data with an unexpected length, i2c_smbus_read_block_data() returns a positive byte count. The function returns this directly, and callers treat any non-negative return as success, processing stale or incomplete buffer contents. Return -EIO when retries are exhausted with a positive return value, preserving the negative error code on I2C failure.
How severe is CVE-2026-46001?
CVE-2026-46001 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-46001 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-46001?
CVE-2026-46001 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-46001?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-46001 have an EU (EUVD) identifier?
Yes. CVE-2026-46001 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32297.
When was CVE-2026-46001 published?
CVE-2026-46001 was published on 2026-05-27 and last updated on 2026-06-17.

References

Affected products (1)

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