Qdrant 1.20 closes an open cluster port rated 9.8, but only if you have set an API key

Qdrant, the Rust vector database behind many retrieval stacks, released v1.20.0 on 22 October with an advisory it rates Critical, 9.8. There is no CVE yet.

The cluster port

In distributed mode, Qdrant peers talk over an internal gRPC port, 6335 by default. Before 1.20 it required no authentication unless you had switched on service.enforce_internal_auth, which was off by default. It also listens on the same address as the public API. Qdrant says a host that can reach it, with no API key, can add a peer and receive replicated shards, rewrite cluster state through Raft messages, or send oversized messages that exhaust memory. Single-node installs do not open the port.

From 1.20, enforcement is on by default, but only when an API key is configured. A cluster with no API key stays open on 6335, and 1.20 adds no message-size limit.

What to do

1. Firewall 6335 so only cluster peers reach it. Qdrant’s advice: if your app servers can reach 6333, check that they cannot reach 6335.
2. Set the same api_key on every peer, enable internal auth and TLS, and restart one peer at a time.
3. On 1.19.2 or later, bind cluster.p2p.host to a private IP.
4. Upgrade one minor at a time, 1.18.x to 1.19.x to 1.20.0. Clusters with only a read_only_api_key lose peer traffic unless you add api_key or turn enforcement off.

Qdrant says Managed Cloud is not materially affected. Hybrid and Private Cloud depend on your network plugin.

The features

The blog leads with BM25 scoring directly on a full-text index, so payload text becomes keyword-searchable without embeddings, plus a new code tokenizer. There are also turbo16 and turbo8 vector types, per-element nested indexes (7 to 38 times faster on Qdrant’s test), and inline storage that no longer keeps a second copy of vectors. Inline vectors now follow the index’s memory tier, so check RAM before upgrading.