CVE-2026-43009: bpf: Fix incorrect pruning due to atomic fetch precision tracking
bpf: Fix incorrect pruning due to atomic fetch precision tracking
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
Extend BPF_LDX handling in backtrack_insn to correctly account for non-stack memory and atomic fetch variants (covering all fetch variants and atomic fetch operations via is_atomic_fetch_insn() helper) so verifier path pruning does not incorrectly consider equivalent branches when atomic fetch precision tracking differs in terms of stack state.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-43009?
CVE-2026-43009 has been classified with a medium severity due to its potential impact on atomic fetch precision tracking.
How do I fix CVE-2026-43009?
To fix CVE-2026-43009, update your Linux kernel to the latest stable version that addresses this vulnerability.
What types of systems are affected by CVE-2026-43009?
CVE-2026-43009 affects the Linux kernel across various distributions and versions.
What is the impact of CVE-2026-43009?
CVE-2026-43009 may lead to incorrect data handling in applications utilizing BPF due to flawed atomic fetch precision tracking.
When was CVE-2026-43009 reported?
CVE-2026-43009 was officially documented and addressed in patches released in 2026.