CVE-2026-98046 Linux CVE debrief

Who should care

Defenders responsible for Linux kernel deployments, particularly those using BPF helpers, should assess their exposure and prioritize verification of BPF helper usage. This includes reviewing and updating BPF program implementations to ensure compatibility and verifying sleepable context for bpf_btf_find_by_name_kind() calls.

Why it matters

A vulnerability in the Linux kernel has been resolved, where the bpf_btf_find_by_name_kind() function was not marked as sleepable, potentially leading to issues when allocating or expanding the current task fd table. Defenders responsible for Linux kernel deployments, particularly those using BPF helpers, should assess their exposure and prioritize verification of BPF helper usage.

• Verification of BPF helper usage in Linux kernel deployments is required to ensure compatibility.
• Defenders should assess exposure to this vulnerability and prioritize remediation.

Technical summary

The bpf_btf_find_by_name_kind() function in the Linux kernel was not marked as sleepable, potentially leading to issues when allocating or expanding the current task fd table. The function has been updated to mark it as sleepable, preserving calls from the main body of a sleepable syscall program while rejecting calls from its non-sleepable regions. This change ensures compatibility and prevents potential issues in Linux kernel deployments using BPF helpers. Defenders should assess exposure and prioritize verification of BPF helper usage.

Defensive priority

Defenders should assess exposure and prioritize verification of BPF helper usage in their Linux kernel deployments.

Recommended defensive actions

• Assess BPF helper usage in Linux kernel deployments
• Verify sleepable context for bpf_btf_find_by_name_kind() calls
• Review and update BPF program implementations to ensure compatibility
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• 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.

Evidence notes

The CVE record and NVD entry provide limited information about the vulnerability, with the primary source being the Linux kernel patch notes. The vulnerability was resolved by marking the bpf_btf_find_by_name_kind() function as sleepable. This change preserves calls from the main body of a sleepable syscall program while rejecting calls from its non-sleepable regions. Defenders should verify BPF helper usage in their Linux kernel deployments to ensure compatibility.

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.