What is CVE-2026-40971?

CVE-2026-40971 is a medium-severity vulnerability in Spring Boot, classified under Improper Certificate Validation. CVSS score: 5.0/10. Published 2026-04-27.

How severe is CVE-2026-40971?

Medium severity. CVSS v3 base score is 5.0 out of 10.

Vulnerability in Spring Boot

CVE-2026-40971

When configured to use an SSL bundle, Spring Boot's RabbitMQ auto-configuration does not perform hostname verification when connecting to the RabbitMQ broker. Affected: Spring Boot 4.0.0–4.0.5 (fix 4.0.6), 3.5.0–3.5.13 (fix 3.5.14) per ve…

Vulnerability class: Improper Certificate Validation

EPSS: 0.001 (19.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Spring Boot — versions 4.0.0, 3.5.0
Vmware Spring_boot

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

security@vmware.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-40971?: CVE-2026-40971 is a medium-severity vulnerability in Spring Boot, classified under Improper Certificate Validation. CVSS score: 5.0/10. Published 2026-04-27.
How severe is CVE-2026-40971?: Medium severity. CVSS v3 base score is 5.0 out of 10.