CVE-2026-72441 Linux CVE debrief

Who should care

Linux kernel developers and users, especially those using ieee802154, should review the patch and apply it to their systems. They should also monitor kernel updates for further fixes and review compensating controls for exposed systems. Additionally, they should check relevant monitoring, detection, and logs for exposed assets that need extra review.

Technical summary

The vulnerability occurs because the `pan_id` field of `struct ieee802154_addr` is left uninitialized when the address mode is `IEEE802154_ADDR_NONE`. This uninitialized `pan_id` is later copied into a `struct sockaddr_ieee802154` in `dgram_recvmsg()` via `ieee802154_addr_to_sa()`, and finally copied to user space, leaking the uninitialized bytes. To address this, the `memset` function is used to zero out the address structure in `ieee802154_hdr_get_addr()` when the mode is `IEEE802154_ADDR_NONE`.

Defensive priority

Medium

Recommended defensive actions

• Apply the patch to zero out the address structure in `ieee802154_hdr_get_addr()` when the mode is `IEEE802154_ADDR_NONE`
• Use memory-safe tools to detect similar issues
• Monitor kernel updates for further fixes
• Review compensating controls for exposed systems
• 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 issue was reported by KMSAN and was resolved by using `memset` to zero out the address structure in `ieee802154_hdr_get_addr()` when the mode is `IEEE802154_ADDR_NONE`. To verify, defenders should review the Linux kernel source code, specifically the `ieee802154_hdr_get_addr()` function, and check for the `memset` call. Additionally, they should monitor kernel updates for further fixes and review compensating controls for exposed systems.

Official resources