CVE-2025-37730

Logstash Improper Certificate Validation in TCP output

MEDIUM
6.5
CVSS Score
Published: May 6, 2025 at 05:29 PM UTC
Updated: June 17, 2026 at 09:15 AM UTC
1 product affected across 1 vendorLogstash

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Logstash· Elasticelastic-plugin
60%
8.0.0 ≤ v < 8.17.68.18.0 ≤ v < 8.18.19.0.0 ≤ v < 9.0.18.0.08.18.09.0.0
Affected range stops below 8.17.6, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.18.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.0.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMelastic
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-295

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