---
id: CVE-2026-40992
title: Spring Boot's Mail auto-configuration does not enable hostname verification
summary: >-
  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 version…
severity: medium
cvss: 5
cvssVector: 'CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L'
cwe:
  - CWE-295
vendor: vmware
product: spring_boot
affected:
  - 'spring_boot >= 3.4.0, < 3.4.17'
  - 'spring_boot >= 3.5.0, < 3.5.14.1'
  - 'spring_boot >= 4.0.0, < 4.0.6.1'
patched:
  - spring_boot 4.0.6.1
published: '2026-06-11'
updated: '2026-09-04'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-40992'
references:
  - url: 'https://spring.io/security/cve-2026-40992'
    label: security@vmware.com
tags:
  - nvd
epss: 0.00124
epssPercentile: 0.02432
ingestedAt: '2026-09-05T13:39:55.204Z'
---

## Overview

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

- `spring_boot >= 3.4.0, < 3.4.17`
- `spring_boot >= 3.5.0, < 3.5.14.1`
- `spring_boot >= 4.0.0, < 4.0.6.1`

## Remediation

Upgrade past the affected range:

- `spring_boot 4.0.6.1`