CVE-2026-40992 — MEDIUM (5.0)

Vulnerability Description

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.

CVSS Score

5.0

MEDIUM

CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Attack Vector

ADJACENT_NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

LOW

Availability

LOW

Related Weaknesses (CWE)

CWE-295

References

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

FAQ

What is CVE-2026-40992?

CVE-2026-40992 is a vulnerability with a CVSS score of 5.0 (MEDIUM). 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...

How severe is CVE-2026-40992?

CVE-2026-40992 has been rated MEDIUM with a CVSS base score of 5.0/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-40992?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.