CVE-2026-98767 usb: dwc3: gadget: fix IRQ storm on invalid event buffer count
A local attacker with high privileges can trigger a kernel panic via an IRQ storm in the DWC3 USB gadget driver by writing invalid values to hardware registers.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98767?
CVE-2026-98767 is a denial of service vulnerability in Linux, published on 18 Oct 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:
usb: dwc3: gadget: fix IRQ storm on invalid event buffer count
When dwc3_check_event_buf() reads a GEVNTCOUNT value exceeding the event buffer length, commit 63ccd26cd1f6 ("usb: dwc3: gadget: check that event count does not exceed event buffer length") returns IRQ_NONE without writing back GEVNTCOUNT. Since the DWC3 interrupt is level-triggered, the uncleared IRQ source keeps the line asserted, causing a tight IRQ storm that accumulates 99,900 unhandled interrupts and triggers spurious.c:184 BUG -> kernel panic.
The resulting call stack: __report_bad_irq+0xac/0xc8 note_interrupt+0x340/0x468 handle_irq_event+0xac/0xc0 handle_fasteoi_irq+0x120/0x228 gic_handle_irq+0x68/0x108 ... kernel BUG at kernel/irq/spurious.c:184
To reproduce, write a bogus value exceeding the event buffer length directly to the GEVNTCOUNT register:
devmem <DWC3_BASE + 0xc40c> 4 0x1004
Write the bogus count back to GEVNTCOUNT to clear the IRQ source, consistent with the stale event clearing pattern in dwc3_event_buffers_setup(), and schedule error recovery to reinitialize the controller.
Which versions are affected by CVE-2026-98767?
How do I fix CVE-2026-98767?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-98767 being exploited?
There is no known exploitation of CVE-2026-98767 in the wild and no public exploit code.
Sources
Also known as AZL-108912, BELL-CVE-2026-98767, DEBIAN-CVE-2026-98767, GHSA-7v54-4578-623x, UBUNTU-CVE-2026-98767.