CVE-2026-31682 Linux CVE debrief

Who should care

System administrators and users of Linux kernel versions 4.15 through 7.0-rc6 should be aware of this vulnerability and take steps to mitigate it. This includes applying available patches, inventorying and updating affected systems, monitoring network traffic for suspicious activity, and verifying system configurations and exception tracking.

Technical summary

The br_nd_send function in the Linux kernel's bridge component did not ensure that neighbour discovery options were in the linear part of the network packet. This could lead to out-of-bounds data access when parsing these options. The issue has been addressed with multiple patches available for various kernel versions. The CVE record was published on 2026-04-25T09:16:01.913Z and last modified on 2026-07-14T13:18:48.683Z.

Defensive priority

High

Recommended defensive actions

• Apply the available patches for the Linux kernel
• Inventory and update affected systems
• Monitor network traffic for suspicious activity
• Consider implementing compensating controls
• Verify system configurations and exception tracking
• Review relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-04-25T09:16:01.913Z and last modified on 2026-07-14T13:18:48.683Z. The NVD entry is currently Modified. This issue is related to the Linux kernel and has been resolved with multiple patches available. The br_nd_send function did not properly linearize the network packet before parsing neighbour discovery options, potentially allowing for out-of-bounds data access.

Official resources