Enabling the RX Buffer Unavailable (RBUE) interrupt in the XGMAC2 driver causes a runaway loop of interrupts whenever DMA runs out of receive descriptors. The loop can produce billions of interrupts for only a few million processed packets, exhausting CPU cycles and preventing normal packet reception. Because the RBUE handler merely sets a flag that the RIE handler already performs, the additional interrupt offers no recovery value and instead triggers a continuous, heavy interrupt storm that can effectively freeze the system for network traffic. The same storm will persist even when the page pool is exhausted, as the DMA remains suspended and RBUE continues to fire, with no forward progress. Consequently, the vulnerability creates a high‑impact denial‑of‑service condition tied to NIC traffic load.

The issue impacts Linux kernel builds that support XGMAC2 devices, specifically noted on the Agilex5 platform. Any kernel using the stmmac driver with the default RBUE interrupt enabled will experience the interrupt storm under heavy RX pressure. The patch removes RBUE from the default interrupt masks across XGMAC2 variants, but the affected devices and kernel versions are not explicitly enumerated in the advisory. Users running kernel versions that include the unmodified XGMAC2 driver should be aware that their NIC may be susceptible to this resource exhaustion behavior during heavy inbound traffic.

Available CVSS data is not provided and EPSS is not available, indicating an undefined but potentially high likelihood of exploitation. The vulnerability is not listed in the CISA KEV catalog, suggesting no known public exploits at this time. However, the attack surface requires access to the NIC for heavy traffic injection, allowing a local or remote attacker with sufficient traffic control to trigger a denial‑of‑service event through continuous NIC interrupts. No special privileges are required beyond the ability to flood the network interface, making this a practical, high‑impact denial‑of‑service vector for systems exposed to uncontrolled inbound traffic.