CVE-2026-98625

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: flowtable: publish HW_DEAD after worker is done

flow_offload_work_del() sets NF_FLOW_HW_DEAD before the work handler

clears NF_FLOW_HW_PENDING. Once a flow is both HW_DYING and HW_DEAD, a

concurrent garbage collection pass can remove it and schedule it for RCU

freeing.

The offload worker holds neither an RCU read lock nor a reference to the

flow. If it is preempted after publishing HW_DEAD, the RCU callback can

free the flow before the worker resumes and clears HW_PENDING, resulting

in a use-after-free.

Move HW_DEAD publication to the common worker epilogue after the pending

bit is cleared, making it the final flow access by destroy work. Order all

preceding flow accesses before publishing the bit that allows garbage

collection to free the object.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References