---
id: "CVE-2026-98528"
kind: "vulnerability"
aliases: ["CVE-2026-98528"]
title: "Linux kernel: GPIO character device error path leaks kernel stack bytes"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["embedded", "gpio", "infrastructure", "linux-kernel"]
not_affected_if: ["no-gpio-chardev"]
published_at: "2026-10-18T16:17:04+00:00"
first_seen_at: "2026-10-23T21:57:15+00:00"
updated_at: "2026-10-25T05:25:07+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98528", "first_seen_at": "2026-10-23T21:57:15+00:00"}]
---

# Linux kernel: GPIO character device error path leaks kernel stack bytes

When the GPIO chip guard cannot be acquired, the GPIO line info ioctl returns before clearing its output struct, so uninitialized kernel stack contents can be copied to user space. An attacker with access to the GPIO character device could read leftover kernel stack memory, which may contain pointers or other sensitive data.

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

## How to check

- unknown

## Fix

- Update to a Linux kernel release that includes the upstream gpio: cdev fix (version unknown from sources)

## Timeline

- 2026-10-23T21:57:15+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98528

## From the sources

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

gpio: cdev: fix kernel stack leak to user-space in error path

If we fail to acquire the GPIO chip guard in gpio_desc_to_lineinfo(), we
return immediately before zeroing the info struct we'll end up passing
to the user-space later in lineinfo_get_v1(). This may leak the kernel
stack contents. Make gpio_desc_to_lineinfo() return int so that the
-ENODEV returned on failure to acquire the guard can be propagated to
the callers.

While not strictly necessary: move the memset() before trying to acquire
the SRCU read lock too for good measure.

---

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