Envoy is a cloud-native, open source edge and service proxy. When an upstream TLS cluster is used with autosni enabled, a request containing a host/:authority header longer than 255 characters triggers an abnormal termination of Envoy process. Envoy does not gracefully handle an error when setting SNI for outbound TLS connection. The error can occur when Envoy attempts to use the host/:authority header value longer than 255 characters as SNI for outbound TLS connection. SNI length is limited to 255 characters per the standard. Envoy always expects this operation to succeed and abnormally aborts the process when it fails. This vulnerability is fixed in 1.30.1, 1.29.4, 1.28.3, and 1.27.5.

A vulnerability was found in Envoy version 1.13.0 or earlier may consume excessive amounts of memory when proxying HTTP/1.1 requests or responses with many small (i.e. 1 byte) chunks.

A vulnerability was found in Envoy version 1.13.0 or earlier may consume excessive amounts of memory when responding internally to pipelined requests.

A vulnerability was found in Envoy. where TLS inspector could have been bypassed (not recognized as a TLS client) by a client using only TLS 1.3. Because TLS extensions (SNI, ALPN) were not inspected, those connections might have been matched to a wrong filter chain, possibly bypassing some security restrictions in the process.

A vulnerability was found in Envoy, where using SDS with Combined Validation Context Using the same secret (e.g. trusted CA) across many resources together with the combined validation context could lead to the “static” part of the validation context to be not applied, even though it was visible in the active config dump.