High · published March 26, 2026
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.14 and 2.12.5, if the nats-server has the "leafnode" configuration enabled (not default), then anyone who can connect can crash the nats-server by triggering a panic. This happens pre-authentication and requires that compression be enabled (which it is, by default, when leafnodes are used). Versions 2.11.14 and 2.12.5 contain a fix. As a workaround, disable compression on the leafnode port.
| Product | Versions | Fixed in |
|---|---|---|
| linuxfoundation/nats-server | < 2.11.14 | 2.11.14 |
| linuxfoundation/nats-server | ≥ 2.12.0, < 2.12.5 | 2.12.5 |