CVE-2026-40970
Description
A flaw was found in Spring Boot. When configured to use an SSL (Secure Sockets Layer) bundle, the Elasticsearch auto-configuration component does not perform hostname verification when establishing a connection to the Elasticsearch server. An attacker on an adjacent network could exploit this by performing a man-in-the-middle attack. This could lead to the disclosure or modification of sensitive information exchanged between Spring Boot and the Elasticsearch server.
Mitigation
To mitigate the risk of man-in-the-middle attacks, ensure that network communication between Spring Boot applications and Elasticsearch servers is protected. This can be achieved by deploying these components on a trusted, isolated network segment or by implementing strict firewall rules to limit access to the Elasticsearch server only from authorized Spring Boot application instances.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.2 | N/A | 5 |
| Attack Vector | Adjacent Network | N/A | Adjacent Network |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | Low |
Vector
Red Hat: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
cve.org: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Understanding the Weakness (CWE)
Integrity,Authentication
Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity
When a certificate is invalid or malicious, it might allow an attacker to spoof a trusted entity by interfering in the communication path between the host and client. The product might connect to a malicious host while believing it is a trusted host, or the product might be deceived into accepting spoofed data that appears to originate from a trusted host.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.