CVE-2026-74475 Linux CVE debrief

Who should care

Linux kernel developers, administrators, and users who rely on the Linux kernel for their systems, as well as security teams and vulnerability management teams, should be aware of this vulnerability and take necessary actions to mitigate its impact.

Technical summary

The Linux kernel vulnerability CVE-2026-74475 is related to the vxlan: use neigh_ha_snapshot() in route_shortcircuit() fix. The neighbour hardware address n->ha can be updated asynchronously by the neighbour subsystem, protected by n->ha_lock seqlock. Reading n->ha without holding the seqlock loop can lead to torn reads or reading a partially updated MAC address. The vxlan: use neigh_ha_snapshot() in route_shortcircuit() fix ensures safe copying of n->ha under read_seqbegin()/read_seqretry() lock protection before using it. This fix is crucial for maintaining the security and stability of Linux kernel-based systems.

Defensive priority

Medium

Recommended defensive actions

• Review and apply the provided kernel patches to ensure the vxlan: use neigh_ha_snapshot() in route_shortcircuit() fix is implemented.
• Monitor Linux kernel updates for any related security patches or advisories.
• Perform regular vulnerability assessments and penetration testing to identify potential issues.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check 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.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and NVD entry provide limited information about the vulnerability. Further analysis is needed to fully understand the issue and its potential impact. The vxlan: use neigh_ha_snapshot() in route_shortcircuit() fix addresses a potential issue with reading the neighbour hardware address n->ha without holding the seqlock loop, which can lead to torn reads or reading a partially updated MAC address. Linux kernel developers, administrators, and users who rely on the Linux kernel for their systems should review the provided kernel patches to ensure the vxlan: use neigh_ha_snapshot() in route_shortcircuit() fix is implemented. They should also monitor Linux kernel updates for any related security patches or advisories and perform regular vulnerability assessments and penetration testing to identify potential issues.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.