An error in the Linux kernel's generic 8250 driver causes a stuck RX‑timeout interrupt on NXP LPC32xx UART hardware. When the FIFO is empty, the interrupt remains set but the driver does not clear it because the driver only reads the FIFO when data is present. This leads to a continuous interrupt storm that locks up the single‑core CPU, rendering the system unresponsive. The flaw is a logic error that allows an attacker to trigger a denial‑of‑service by repeatedly opening the UART device or continuously forcing the DMA to generate the timeout condition.

Linux kernel builds that include the generic 8250_of driver and run on NXP LPC32xx family devices such as the PORT_LPC3220. The issue is not present in board‑specific 8250 drivers that already implement a custom interrupt handler. Systems that expose the UART to userspace, for example by providing a /dev/ttyS1 console, are directly affected.

The vulnerability is not currently listed in the Adaptive Threat Intelligence EPSS database, and it lacks a CEAs CVSS score in the CVE record. However, the described behaviour—continuous CPU hogging and a soft‑lockup—indicates a high impact denial‑of‑service. The attack vector is local; it requires the ability to open the serial port or otherwise trigger the timeout interrupt, which is typically available to any user on the system. Since the KEV catalog does not list the vulnerability, no publicly known exploits are available as of this analysis, but the flaw could be leveraged by an attacker with any privilege level to lock the host.