CVE-2026-64587 net: ethernet: arc: emac: quiesce interrupts before requesting IRQ
A race condition in the ARC EMAC Ethernet driver allows stale interrupts to cause a use-after-free during probe teardown, leading to system crashes.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64587?
CVE-2026-64587 is a high-severity vulnerability in Linux, published on 6 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: arc: emac: quiesce interrupts before requesting IRQ
Normal RX/TX interrupts are enabled later, in arc_emac_open(), so probe should not see interrupt delivery in the usual case. However, hardware may still present stale or latched interrupt status left by firmware or the bootloader.
If probe later unwinds after devm_request_irq() has installed the handler, such a stale interrupt can still reach arc_emac_intr() during teardown and race with release of the associated net_device.
Avoid that window by putting the device into a known quiescent state before requesting the IRQ: disable all EMAC interrupt sources and clear any pending EMAC interrupt status bits. This keeps the change hardware-focused and minimal, while preventing spurious IRQ delivery from leftover state.
Which versions are affected by CVE-2026-64587?
How do I fix CVE-2026-64587?
Apply the vendor's patch.
Is CVE-2026-64587 being exploited?
There is no known exploitation of CVE-2026-64587 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-64587, DEBIAN-CVE-2026-64587, GHSA-9p7c-hfwg-795w, UBUNTU-CVE-2026-64587.