The NATS official Rust clients are vulnerable to MitM when using TLS.
The common name of the server's TLS certificate is validated against the host
name provided by the server's plaintext INFO
message during the initial connection setup phase. A MitM proxy can tamper with the host
field's value by substituting it with the common name of a valid certificate it controls, fooling the client into accepting it.
INFO
messageINFO
, alters the host
JSON field and passes the tampered INFO
back to the clienthost
was set to the common name of said certificaterustls
accepts the certificate, having verified that the common name matches the attacker-controlled value it was given{ "nvd_published_at": null, "cwe_ids": [], "severity": "MODERATE", "github_reviewed": true, "github_reviewed_at": "2023-03-24T21:59:53Z" }