Cyber Resilience

CVE-2025-34227

RCE in Nagios Xi ≤ 2026

Published
25 September 2025
Modified
14 October 2025
Patch / advisory
CVSS Score v4 8.6
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.24 98th percentile
Risk Priority 45 floored blend · peak EPSS

Summary

CVE-2025-34227 is a high-severity OS Command Injection (CWE-78) vulnerability in Nagios Nagios Xi. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Nagios XI versions prior to 2026R1 contain an authenticated command injection vulnerability in the MongoDB Database, MySQL Query, MySQL Server, Postgres Server, and Postgres Query configuration wizards. The flaw, tracked as CWE-78, permits injection of shell metacharacters into user-supplied arguments passed to these services, resulting in execution of arbitrary operating system commands on the host as the nagios user. The issue carries a CVSS 4.0 score of 8.6 with network attack vector, low complexity, and high impact on confidentiality, integrity, and availability.

An attacker with a valid administrative account on Nagios XI can reach the affected wizards over the network and supply crafted input that escapes the intended command context. Successful exploitation grants the ability to run any system command under the nagios account, potentially leading to full host compromise within the privileges of that user.

Public references, including the Nagios changelog and security pages, indicate that the issue is resolved in release 2026R1; administrators are expected to apply the update to eliminate the vulnerable wizards. The associated EPSS score remains flat at 0.0465 with no observed increase after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Nagios XI < 2026R1 is vulnerable to an authenticated command injection vulnerability within the MongoDB Database, MySQL Query, MySQL Server, Postgres Server, and Postgres Query wizards. It is possible to inject shell characters into arguments provided to the service and…

more

execute arbitrary system commands on the underlying host as the `nagios` user.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-34134Same product: Nagios Nagios Xi
CVE-2024-14005Same product: Nagios Nagios Xi
CVE-2026-2042Same product: Nagios Nagios Xi
CVE-2019-15949Same product: Nagios Nagios Xi
CVE-2018-8735Same product: Nagios Nagios Xi
CVE-2024-14003Same product: Nagios Nagios Xi
CVE-2024-14008Same product: Nagios Nagios Xi
CVE-2025-34286Same product: Nagios Nagios Xi
CVE-2026-2041Same product: Nagios Nagios Xi
CVE-2026-2043Same product: Nagios Nagios Xi

Affected Assets

nagios
nagios xi
≤ 2026

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect command sanitization during development.

Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.

Least privilege reduces the permissions available to any process that could be subverted by injected commands.

Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.

Secure engineering principles require proper neutralization of untrusted input before command construction.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References