Mail Auto-Configuration Does Not Enable SSL Hostname Verification
CVE-2026-40992

5MEDIUM

Key Information:

Vendor

Spring

Status
Spring Boot
Vendor
CVE Published:
11 June 2026

What is CVE-2026-40992?

Spring Boot's Mail auto-configuration does not enable hostname verification. Applications that set the relevant JavaMail property, such as spring.mail.properties.mail.smtp.ssl.checkserveridentity=true, are not affected.

Affected versions: Spring Boot 4.0.0 through 4.0.6; 3.5.0 through 3.5.14; 3.4.0 through 3.4.16.

Affected Version(s)

Spring Boot 4.0.0 < 4.0.7

Spring Boot 3.5.0 < 3.5.15

Spring Boot 3.4.0 < 3.4.17

References

https://spring.io/security/cve-2026-40992

CVSS V3.1

Score:
5
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Adjacent Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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