A race condition occurs in the Linux kernel’s cortina driver for Gemini Ethernet adapters. The driver uses a static local receive buffer to assemble fragmented packets, and because the device has two physical ports, concurrent traffic on those ports can access the same buffer, leading to improper memory use. This concurrency flaw can corrupt memory and, in the worst case, cause a kernel panic. The weakness is classified as CWE‑820, indicating inadequate handling of infrastructural data.

The vulnerability impacts any Linux system whose kernel contains the cortina driver without the per‑port RX buffer change. It specifically targets the Gemini Ethernet adapter, which has two ports. Since no version range is specified, any kernel snapshot built with the cortina driver prior to the per‑port fix may be vulnerable; therefore, all distributions using the default mainline kernel are potentially affected until the update is applied.

The CVSS score of 9.8 signals a high severity, yet the EPSS score is below 1 %, suggesting limited evidence of exploitation in the wild. The flaw is not listed in the CISA KEV catalog. An attacker could trigger the race by generating traffic on both NIC ports simultaneously, potentially leading to a kernel panic or memory corruption. Although the exploitation path is straightforward for a knowledgeable attacker with network access to the NIC, the attack requires precise timing of the reassembly window. Due to the severe potential impact, prompt mitigation is advised.