The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. A user with access to the Kubernetes cluster can use a path traversal attack to execute Envoy Admin interface commands on proxies managed by any version of Envoy Gateway prior to 1.2.6. The admin interface can be used to terminate the Envoy process and extract the Envoy configuration (possibly containing confidential data). Version 1.2.6 fixes the issue. As a workaround, the `EnvoyProxy` API can be used to apply a bootstrap config patch that restricts access strictly to the prometheus stats endpoint. Find below an example of such a bootstrap patch.

Envoy is a cloud-native high-performance edge/middle/service proxy. In affected versions envoy does not properly handle http 1.1 non-101 1xx responses. This can lead to downstream failures in networked devices. This issue has been addressed in versions 1.31.5 and 1.32.3. Users are advised to upgrade. There are no known workarounds for this issue.

Envoy is a cloud-native high-performance edge/middle/service proxy. In affected versions `sendOverloadError` is going to assume the active request exists when `envoy.load_shed_points.http1_server_abort_dispatch` is configured. If `active_request` is nullptr, only onMessageBeginImpl() is called. However, the `onMessageBeginImpl` will directly return ok status if the stream is already reset leading to the nullptr reference. The downstream reset can actually happen during the H/2 upstream reset. As a result envoy may crash. This issue has been addressed in releases 1.32.3, 1.31.5, 1.30.9, and 1.29.12. Users are advised to upgrade. Users unable to upgrade may disable `http1_server_abort_dispatch` load shed point and/or use a high threshold.

Envoy is a cloud-native high-performance edge/middle/service proxy. When additional address are not ip addresses, then the Happy Eyeballs sorting algorithm will crash in data plane. This issue has been addressed in releases 1.32.2, 1.31.4, and 1.30.8. Users are advised to upgrade. Users unable to upgrade may disable Happy Eyeballs and/or change the IP configuration.

Envoy is a cloud-native high-performance edge/middle/service proxy. Envoy will crash when the http async client is handling `sendLocalReply` under some circumstance, e.g., websocket upgrade, and requests mirroring. The http async client will crash during the `sendLocalReply()` in http async client, one reason is http async client is duplicating the status code, another one is the destroy of router is called at the destructor of the async stream, while the stream is deferred deleted at first. There will be problems that the stream decoder is destroyed but its reference is called in `router.onDestroy()`, causing segment fault. This will impact ext_authz if the `upgrade` and `connection` header are allowed, and request mirrorring. This issue has been addressed in versions 1.31.2, 1.30.6, 1.29.9, and 1.28.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Envoy is a cloud-native high-performance edge/middle/service proxy. Jwt filter will lead to an Envoy crash when clear route cache with remote JWKs. In the following case: 1. remote JWKs are used, which requires async header processing; 2. clear_route_cache is enabled on the provider; 3. header operations are enabled in JWT filter, e.g. header to claims feature; 4. the routing table is configured in a way that the JWT header operations modify requests to not match any route. When these conditions are met, a crash is triggered in the upstream code due to nullptr reference conversion from route(). The root cause is the ordering of continueDecoding and clearRouteCache. This issue has been addressed in versions 1.31.2, 1.30.6, and 1.29.9. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Envoy is a cloud-native high-performance edge/middle/service proxy. A vulnerability has been identified in Envoy that allows malicious attackers to inject unexpected content into access logs. This is achieved by exploiting the lack of validation for the `REQUESTED_SERVER_NAME` field for access loggers. This issue has been addressed in versions 1.31.2, 1.30.6, 1.29.9, and 1.28.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Envoy is a cloud-native high-performance edge/middle/service proxy. Envoy's 1.31 is using `oghttp` as the default HTTP/2 codec, and there are potential bugs around stream management in the codec. To resolve this Envoy will switch off the `oghttp2` by default. The impact of this issue is that envoy will crash. This issue has been addressed in release version 1.31.2. All users are advised to upgrade. There are no known workarounds for this issue.

Envoy is a cloud-native high-performance edge/middle/service proxy. A security vulnerability in Envoy allows external clients to manipulate Envoy headers, potentially leading to unauthorized access or other malicious actions within the mesh. This issue arises due to Envoy's default configuration of internal trust boundaries, which considers all RFC1918 private address ranges as internal. The default behavior for handling internal addresses in Envoy has been changed. Previously, RFC1918 IP addresses were automatically considered internal, even if the internal_address_config was empty. The default configuration of Envoy will continue to trust internal addresses while in this release and it will not trust them by default in next release. If you have tooling such as probes on your private network which need to be treated as trusted (e.g. changing arbitrary x-envoy headers) please explicitly include those addresses or CIDR ranges into `internal_address_config`. Successful exploitation cou…