Zephyr Bluetooth Mesh vulnerabilities

A vulnerability in the Bluetooth Mesh stack in Zephyr causes a permanent loss of message contexts from the pool, leading to denial of service (DoS) after pool exhaustion. An attacker in the mesh network can intentionally trigger context leaks, and the device stops responding to requests until reboot.

A vulnerability in the Zephyr Bluetooth Mesh stack affects the Solicitation PDU handler in sol_pdu_decrypt(). Received PDU is copied into a fixed 17-byte stack buffer without length checking, leading to stack overflow in production builds where assertions are disabled. An attacker can send a crafted advertisement to trigger out-of-bounds write without any cryptographic keys.

An integer underflow in bt_mesh_sol_recv() in the Bluetooth Mesh solicitation handling leads to an out-of-bounds write. When CONFIG_BT_MESH_OD_PRIV_PROXY_SRV is enabled, the function parses solicitation PDUs from raw BLE advertising payloads. The AD parsing loop reads an attacker-controlled length byte and computes reported_len - 3 without checking that reported_len >= 3. When reported_len is less than 3, the subtraction yields a negative value that bypasses the length guard and is then implicitly converted to a very large size_t when passed to net_buf_simple_pull_mem(). In builds without assertions, this wraps the buffer length and advances the data pointer far out of bounds, so subsequent reads dereference invalid memory. A nearby BLE device can trigger this with a non-connectable advertisement carrying a UUID16 AD structure and a crafted length byte, with no pairing or prior association required, potentially leading to denial of service or arbitrary code execution.