---
id: "CVE-2026-98656"
kind: "vulnerability"
aliases: ["CVE-2026-98656"]
title: "Linux kernel IIO: deferred trigger work can touch freed memory"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["embedded", "iio", "infrastructure", "linux-kernel"]
not_affected_if: ["no-iio-triggers"]
published_at: "2026-10-18T16:17:18+00:00"
first_seen_at: "2026-10-23T21:57:16+00:00"
updated_at: "2026-10-25T05:19:35+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98656", "first_seen_at": "2026-10-23T21:57:16+00:00"}]
---

# Linux kernel IIO: deferred trigger work can touch freed memory

The Linux kernel's IIO trigger subsystem can leave a deferred work item armed after the trigger is freed, so the worker later reads freed memory. The sources do not state what an attacker can gain from this use-after-free.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- unknown

## Fix

- Install a Linux kernel release that includes the upstream commit adding cancel_work_sync on trig->reenable_work in iio_trig_release(); the sources do not name the fixed version numbers.

## Timeline

- 2026-10-23T21:57:16+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98656

## From the sources

In the Linux kernel, the following vulnerability has been resolved:

iio: trigger: cancel reenable_work before freeing trigger

iio_trigger_notify_done_atomic() defers ->reenable() into
trig->reenable_work on the system workqueue, and the worker dereferences
the owning trigger through container_of().  Nothing cancels this work
before iio_trig_release() frees the trigger, so a worker armed by the
last in-flight IRQ can outlive the free and touch freed memory.

Cancel it at the top of iio_trig_release(), which every free path
reaches through the device core's final put_device().

Found by an in-house static analysis tool.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_