1.35.1 (August 19, 2025)

Incompatible behavior changes

Changes that are expected to cause an incompatibility if applicable; deployment changes are likely required

• ext_proc: Reverted https://github.com/envoyproxy/envoy/pull/39740 to re-enable fail_open+FULL_DUPLEX_STREAMED configuraton combination.

Bug fixes

Changes expected to improve the state of the world and are unlikely to have negative effects

• http: Fixed a bug where the premature resets of streams may result in the recursive draining and potential stack overflow. Setting proper max_concurrent_streams value for HTTP/2 or HTTP/3 could eliminate the risk of the stack overflow before this fix.

• listeners: Fixed issue where TLS inspector listener filter timed out when used with other listener filters. The bug was triggered when a previous listener filter processed more data than the TLS inspector had requested, causing the TLS inspector to incorrectly calculate its buffer growth strategy. The fix ensures that buffer growth is now based on actual bytes available rather than the previously requested amount.