In the Linux kernel, the rzg2l_clear_irq_int() and rzg2l_clear_tint_int() functions perform a read‑modify‑write to clear interrupt status bits, assuming the hardware clears bits when written with zero. Because this operation is not atomic, an interrupt that is set between the read and the write can be cleared inadvertently, resulting in lost interrupt events. The impact is the loss of pending interrupts, which can degrade real‑time performance or cause services relying on timely interrupt handling to miss events; it does not enable arbitrary code execution or direct data corruption.

The flaw appears in the irqchip drivers for Renesas RZ‑G2L platforms in the Linux kernel, affecting all kernel releases prior to the commit that implements the write‑back‑with‑ones fix. All distributions shipping a kernel that contains the renesas‑rzg2l driver are potentially impacted; specific versions are not enumerated, so any kernel using this driver before the patch is included.

The EPSS score is reported as less than 1 % and the vulnerability is not listed in CISA’s KEV catalog, indicating a very low probability of exploitation. The likely attack vector involves generating multiple simultaneous GPIO interrupts—such as by using the gpioset command—to force a race condition during interrupt handling. Successful exploitation requires local access to the affected device and relies on a precise timing window, so the risk is moderate for systems where interrupts are critical, but it does not currently provide remote code execution or broader system compromise.