Vulnerability in Elastic Logstash

CVE-2025-37730

Improper certificate validation in Logstash's TCP output could lead to a man-in-the-middle (MitM) attack in “client” mode, as hostname verification in TCP output was not being performed when the ssl_verification_mode => full was set.

Vulnerability class: Improper Certificate Validation

EPSS: 0.001 (25.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-37730?
CVE-2025-37730 is a medium-severity vulnerability in Elastic Logstash, classified under Improper Certificate Validation. CVSS score: 6.5/10. Published 2025-05-06.
How severe is CVE-2025-37730?
Medium severity. CVSS v3 base score is 6.5 out of 10.