v1.37.0

envoyproxy/envoyv1.37.0Jan 13, 2026by publish-envoy[bot]

AI Summary

A major feature release introducing dynamic module expansion for network and UDP filters, new filters like transform and MCP, and significant HTTP/2 performance optimizations. It also enhances the composite filter ecosystem, security features like ext_authz, and observability capabilities.

Key Highlights

  • Dynamic module expansion for network, listener, and UDP filters
  • New transform filter for request/response body modification
  • New MCP (Model Context Protocol) filter for agentic network
  • HTTP/2 performance optimizations including reduced allocations
  • Enhanced ext_authz with error response support and improved header handling

Breaking Changes

  • Changed default HTTP reset code from NO_ERROR to INTERNAL_ERROR
  • Changed reset behavior to ignore upstream protocol errors by default
  • Proto API Scrubber now returns 404 Not Found instead of 403 Forbidden for blocked methods
  • Removed multiple runtime guards and legacy code paths

New Features

  • Streaming HTTP callouts to HTTP filters
  • Network-layer geoip filter
  • Postgres Inspector listener filter
  • Stats-based access logger
  • MaxMind Country database support for geoip

Full Release Notes

## Summary of changes

### Dynamic modules expansion
- Added support for network, listener, UDP listener, and access logger filters
- Introduced streaming HTTP callouts to HTTP filters
- Enhanced ABI for streaming body manipulation and header operations
- Added global module loading and improved module search path handling

### HTTP and protocol enhancements
- Container-aware CPU detection for improved resource utilization in containerized environments
- HTTP/2 performance optimizations including reduced allocations for well-known headers
- Enhanced cookie matching in route configuration
- Added vhost header customization and forward client cert matching via xDS matcher

### Filter ecosystem growth
- New transform filter for request/response body modification
- New MCP (Model Context Protocol) filter and router for agentic network
- Network-layer geoip filter for non-HTTP geolocation
- Postgres Inspector listener filter for PostgreSQL traffic routing

### Security and authorization
- Proto API Scrubber filter now production-ready with comprehensive metrics
- Enhanced ext_authz with error response support and improved header handling
- Better TLS certificate validation failure messages in access logs
- On-demand certificate fetching via SDS

### Composite filter improvements
- Support for filter chains and named filter chains
- Improved scalability through filter chain reuse across match actions

### Observability
- New stats-based access logger
- Process-level rate limiting for access logs
- Enhanced OTLP stats sink with metric dropping support
- Added execution counters and improved tracing support across filters

### Router and traffic management
- Cluster-level retry policies, hash policies, and request mirroring
- Composite cluster extension for retry-aware cluster selection
- Substitution formatting for direct response bodies and descriptor values

### Other notable changes
- Fixed multiple memory leaks and crashes in HTTP/2, Lua, and connection handling
- Improved QUIC path migration using QUICHE logic
- Enhanced TCP proxy with upstream connect mode and early data buffering
- Added MaxMind Country database support for geoip

## Breaking changes

- Changed default HTTP reset code from `NO_ERROR` to `INTERNAL_ERROR`
- Changed reset behavior to ignore upstream protocol errors by default
- Proto API Scrubber now returns `404 Not Found` instead of `403 Forbidden` for blocked methods
- Removed multiple runtime guards and legacy code paths

## Deprecations

- OpenTelemetry access log `common_config` field deprecated in favor of explicit `http_service`/`grpc_service` configuration

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**Docker images**:
    https://hub.docker.com/r/envoyproxy/envoy/tags?page=1&name=v1.37.0
**Docs**:
    https://www.envoyproxy.io/docs/envoy/v1.37.0/
**Release notes**:
    https://www.envoyproxy.io/docs/envoy/v1.37.0/version_history/v1.37/v1.37.0
**Full changelog**:
    https://github.com/envoyproxy/envoy/compare/v1.36.0...v1.37.0

Signed-off-by: Ryan Northey <ryan@synca.io>
Signed-off-by: Boteng Yao <boteng@google.com>