Envoyproxy : Security Vulnerabilities, CVEs, (Memory corruption)

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, gRPC access loggers using listener's global scope can cause a `use-after-free` crash when the listener is drained. Versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12 have a fix for this issue. As a workaround, disable gRPC access log or stop listener update.

Envoy is a cloud-native high-performance edge/middle/service proxy. In versions prior to 1.22.1 if Envoy attempts to send an internal redirect of an HTTP request consisting of more than HTTP headers, there’s a lifetime bug which can be triggered. If while replaying the request Envoy sends a local reply when the redirect headers are processed, the downstream state indicates that the downstream stream is not complete. On sending the local reply, Envoy will attempt to reset the upstream stream, but as it is actually complete, and deleted, this result in a use-after-free. Users are advised to upgrade. Users unable to upgrade are advised to disable internal redirects if crashes are observed.

Envoy is a cloud-native high-performance proxy. Versions of envoy prior to 1.22.1 are subject to a segmentation fault in the GrpcHealthCheckerImpl. Envoy can perform various types of upstream health checking. One of them uses gRPC. Envoy also has a feature which can “hold� (prevent removal) upstream hosts obtained via service discovery until configured active health checking fails. If an attacker controls an upstream host and also controls service discovery of that host (via DNS, the EDS API, etc.), an attacker can crash Envoy by forcing removal of the host from service discovery, and then failing the gRPC health check request. This will crash Envoy via a null pointer dereference. Users are advised to upgrade to resolve this vulnerability. Users unable to upgrade may disable gRPC health checking and/or replace it with a different health checking type as a mitigation.

An issue was discovered in Envoy through 1.71.1. There is a remotely exploitable NULL pointer dereference and crash in TLS when an unknown TLS alert code is received.

Envoy before 1.16.1 mishandles dropped and truncated datagrams, as demonstrated by a segmentation fault for a UDP packet size larger than 1500.

An issue was discovered in Envoy 1.12.0. Upon receipt of a malformed HTTP request without a Host header, it sends an internally generated "Invalid request" response. This internally generated response is dispatched through the configured encoder filter chain before being sent to the client. An encoder filter that invokes route manager APIs that access a request's Host header causes a NULL pointer dereference, resulting in abnormal termination of the Envoy process.

An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the heap outside of the request buffers when the upstream is HTTP/1. This may be used to corrupt nearby heap contents (leading to a query-of-death scenario) or may be used to bypass Envoy's access control mechanisms such as path based routing. An attacker can also modify requests from other users that happen to be proximal temporally and spatially.