An out‑of‑bounds write in the ggml‑rpc RDMA transport’s rdma_recv() function can overflow a one‑byte stack variable in rpc_serve_client(), allowing an unauthenticated remote peer to crash the server or potentially execute arbitrary code. This flaw is a classic stack‑based buffer overflow (CWE‑787) that directly compromises the confidentiality, integrity, and availability of the affected service.

The vulnerability affects builds of the open‑source llama.cpp project from ggml‑org, specifically any version prior to commit b11865; the defect present as early as commit b8841. Users of older releases should verify their code base and update to b11865 or later versions where the buffer boundary check has been corrected.

The CVSS score of 9.2 indicates a critical level of risk. Exploitation requires no authentication: an attacker can advertise RDMA capabilities in the HELLO message and deliver up to 256 KiB of data to the vulnerable stack slot, triggering a crash or possibly arbitrary code execution. With no EPSS data and no KEV listing, the likelihood of attack remains uncertain, but the high severity and public disclosure mean that a determined adversary could mount a remote attack against exposed RPC endpoints.