Cyber Posture

CVE-2025-34271

CriticalPublic PoC

Published: 30 October 2025

Published
30 October 2025
Modified
06 November 2025
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0106 77.7th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Description

Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.

Security Summary

CVE-2025-34271 is a critical vulnerability in Nagios Log Server versions prior to 2024R2.0.2, specifically within the cluster manager component. The issue arises when the component requests sensitive credentials from peer nodes over an unencrypted channel, even if SSL/TLS is enabled in the product configuration. This leads to cleartext transmission of sensitive information, mapped to CWE-319, with a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

An attacker positioned on the network path between cluster nodes, such as in a man-in-the-middle scenario, can intercept these credentials in transit without requiring any privileges or user interaction. Captured credentials allow the attacker to authenticate as a cluster node or service account, facilitating unauthorized access, lateral movement across the network, or complete system compromise.

Nagios advisories recommend upgrading to version 2024R2.0.2 or later to address the vulnerability, as detailed in the product changelog and security page. Further technical analysis is provided in the VulnCheck advisory on the cluster manager's plaintext credential requests.

Details

CWE(s)
CWE-319

Affected Products

nagios
log server
2024 · ≤ 2024

MITRE ATT&CK Enterprise Techniques

T1040 Network Sniffing Credential Access
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network.
T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
Why these techniques?

The vulnerability causes cleartext transmission of sensitive credentials between cluster nodes, directly enabling network sniffing (T1040) to capture them and adversary-in-the-middle (T1557) positioning to intercept them without privileges.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References