Affected: Maven: io.netty:netty-codec-redis

### Summary An attacker can cause DoS by sending a crafted Redis payload with deeply nested arrays. This forces the server to allocate a massive number of state objects and collections, leading to memory exhaustion and an OutOfMemoryError.

### Details io.netty.handler.codec.redis.RedisArrayAggregator aggregates RedisMessage parts into ArrayRedisMessage. It uses a `Deque<AggregateState>` to keep track of nested arrays. However, it does not limit the maximum depth of nested arrays. When an attacker sends a continuous stream of nested array headers (e.g., `*1\r\n*1\r\n*1\r\n...`), RedisArrayAggregator pushes a `new AggregateState` onto the stack and allocates a `new ArrayList` for each header. Because there is no depth limit, an attacker can send millions of such headers. This consumes a massive amount of heap memory for the AggregateState instances and their backing ArrayLists, eventually resulting in an OutOfMemoryError.

### Impact Denial of Service due to memory exhaustion. Any application using Netty's RedisArrayAggregator to handle untrusted Redis traffic is vulnerable.