CVE-2026-72409
CVE-2026-72409 is a security vulnerability in Kernel. O3 Security confirms whether CVE-2026-72409 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
net: mvneta: re-enable percpu interrupt on resume
Real-World Exposure
KernelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Linux packages — download data is not available via public APIs for these ecosystems.
Description
In the Linux kernel, the following vulnerability has been resolved:
net: mvneta: re-enable percpu interrupt on resume
On Marvell MPIC platforms (Armada 370/XP/38x), mvneta uses a percpu IRQ disable/enable scheme for NAPI: the ISR (mvneta_percpu_isr) calls disable_percpu_irq() to mask the MPIC per-CPU interrupt and schedules NAPI poll, which calls enable_percpu_irq() on completion to unmask.
If suspend occurs while NAPI poll is pending (between disable_percpu_irq in the ISR and enable_percpu_irq in poll completion), the interrupt is never re-enabled:
- mvneta_percpu_isr: disable_percpu_irq() + napi_schedule() => MPIC masked, percpu_enabled cpumask bit cleared
- NAPI poll does not complete before suspend proceeds (on PREEMPT_RT this is highly likely since softirqs run in ksoftirqd which gets frozen; on non-RT it can happen when softirq processing is deferred to ksoftirqd)
- mvneta_stop_dev => napi_disable(): cancels the pending poll without executing the completion path
- suspend_device_irqs => IRQCHIP_MASK_ON_SUSPEND: masks MPIC (already masked, but records IRQS_SUSPENDED)
- Resume: mpic_resume checks irq_percpu_is_enabled() => false (bit was cleared in step 1) => skips unmask
- mvneta_start_dev only restores device-level INTR_NEW_MASK, does not touch the MPIC per-CPU mask
Result: MPIC per-CPU interrupt stays masked permanently. The NIC generates interrupts (INTR_NEW_CAUSE != 0) but the CPU never receives them, causing complete loss of network connectivity.
Fix by calling on_each_cpu(mvneta_percpu_enable) in the resume path to unconditionally unmask the MPIC per-CPU interrupt regardless of pre-suspend state.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐧Linux | Kernel | ≥ 4.4.0&&< 5.10.261 | 5.10.261 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Kernel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update Kernel to 5.10.261 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-72409 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-72409 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-72409. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-72409 in your dependencies?
O3 detects CVE-2026-72409 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.