CVE-2020-28900

Insufficient Verification of Data Authenticity in Nagios Fusion 4.1.8 and earlier and Nagios XI 5...

9.8 Critical

Insufficient Verification of Data Authenticity in Nagios Fusion 4.1.8 and earlier and Nagios XI 5.7.5 and earlier allows for Escalation of Privileges or Code Execution as root via vectors related to an untrusted update package to upgrade_to_latest.sh.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

3.12%Up 2.0 points since May 25, 2021

What each source reports

NVD Score used 9.8

Record: CVE-2020-28900
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0: 10.0 HighAV:N/AC:L/Au:N/C:C/I:C/A:C
Weakness: CWE-345
Updated: 2026-11-02

CVE List No score

Record: CVE-2020-28900
Updated: 2026-11-02

EUVDEUVD-2020-21291 No score

Record: EUVD-2020-21291
Updated: 2026-11-03

GitHub AdvisoriesGHSA-j8w7-pmfx-jm24 No score

Insufficient Verification of Data Authenticity in Nagios Fusion 4.1.8 and earlier and Nagios XI 5...

Record: GHSA-j8w7-pmfx-jm24
Weakness: CWE-345
Updated: 2026-11-02

Affected products

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2020-28900 is a critical vulnerability (CVSS 9.8) in Nagios Fusion, published May 24, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.12%, the 87th percentile. No source names a fixed version.