Announcing Istio 1.26.4
Istio 1.26.4 patch release.
This release contains bug fixes to improve robustness. This release note describes what’s different between Istio 1.26.3 and 1.26.4.
This release implements the security updates described in our 3rd of September post, ISTIO-SECURITY-2025-001.
BEFORE YOU UPGRADE
Things to know and prepare before upgrading.
DOWNLOAD
Download and install this release.
DOCS
Visit the documentation for this release.
SOURCE CHANGES
Inspect the full set of source code changes.
Changes
Fixed an issue where
istio-iptableswould sometimes ignore the IPv4 state in favor of the IPv6 state when deciding whether new iptables rules needed to be applied. (Issue #56587)Fixed a bug where our tag watcher code didn’t consider the default revision to be the same as the default tag. This would cause issues where Kubernetes gateways wouldn’t be programmed. (Issue #56767)
Fixed an issue causing Gateway chart installation failures with Helm v3.18.5 due to a stricter JSON schema validator. The chart’s schema has been updated to be compatible. (Issue #57354)
Fixed an issue where the
PreserveHeaderCaseoption was overriding other HTTP/1.x protocol options, such as HTTP/1.0. (Issue #57528)