Vulnerability · Published Apr 27, 2026 · Assigned by vmware
CVE-2026-40970
Medium 5.0
In plain English
A medium-severity improper certificate validation in Spring Boot from Spring. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.0Medium
Exploit odds (30 days)0.1%top 97.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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 Boot 4.0.0–4.0.5; upgrade to 4.0.6 or later per vendor advisory.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | org.springframework.boot:spring-boot-elasticsearch | 4.0.6 | GHSA-c96x-rpm4-349p |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Spring | Spring Boot | 4.0.0 – before 4.0.6 |
Weakness: CWE-295 · Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L