Spring Security Advisories

RSS feed

Elasticsearch auto-configuration with an SSL bundle disables TLS hostname verification

MEDIUM | APRIL 23, 2026 | CVE-2026-40970

Description

When configured to use an SSL bundle, Spring Boot's Elasticsearch auto-configuration does not perform hostname verification when connecting to the Elasticsearch server.

Affected Spring Products and Versions

Spring Boot:

  • 4.0.0 - 4.0.5

Mitigation

Users of affected versions should upgrade to the corresponding fixed version.
Fix versionAvailability
4.0.6OSS

No further mitigation steps are necessary.

Credit

The issue was identified and responsibly reported by Yu Bao (@August829) - [email protected] – who works for paypal.com.

References

History

  • 2026-04-23: Initial vulnerability report published.

Reporting a vulnerability

To report a security vulnerability for a project within the Spring portfolio, see the Security Policy

Get ahead

VMware offers training and certification to turbo-charge your progress.

Learn more

Get support

Tanzu Spring offers support and binaries for OpenJDK™, Spring, and Apache Tomcat® in one simple subscription.

Learn more

Upcoming events

Check out all the upcoming events in the Spring community.

View all