CVE-2026-64037 Linux CVE debrief

Who should care

Linux kernel users and administrators should be aware of this vulnerability and take steps to ensure their systems are updated with the latest kernel patches. They should also verify that the system is running with the latest kernel patches and monitor system logs for potential exploitation attempts.

Technical summary

The vulnerability is caused by the MLD driver's failure to detect the sentinel value of max_tid_amsdu_len set to 1 when AMSDU is disabled. This allows the TSO segmentation path to calculate a zero num_subframes value, leading to a large number of tiny segments being created from a single GSO skb. The MVM driver is not affected as it checks mvmsta->amsdu_enabled before reaching the num_subframes calculation.

Defensive priority

High

Recommended defensive actions

• Update the Linux kernel to the latest version
• Verify that the system is running with the latest kernel patches
• Monitor system logs for potential exploitation attempts
• 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 was published on 2026-07-19T16:17:43.947Z and has not been modified since then. The NVD entry is currently Received. The Linux kernel's iwlwifi component has a vulnerability that can cause a TSO segmentation explosion when AMSDU is disabled. This can lead to memory corruption and a subsequent use-after-free in TCP's retransmit queue. The vulnerability is caused by the MLD driver's failure to detect the sentinel value of max_tid_amsdu_len set to 1 when AMSDU is disabled.

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.