CVE-2020-28900

Name: CVE-2020-28900
Creator: NVD / NIST
Published: 2021-05-24T13:15:07.617+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 2.36%

Last modified Jun 17, 2026

CVE-2020-28900 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 2.36% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.36%

81.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-345

Affected Software

Vendor	Product	Versions
Nagios	Fusion	<= 4.1.8
Nagios	Nagios Xi	<= 5.7.5

References

http://packetstormsecurity.com/files/162783/Nagios-XI-Fusion-Privilege-Escalation-Cross-Site-Scripting-Code-Execution.htmlThird Party Advisory, VDB Entry
https://skylightcyber.com/2021/05/20/13-nagios-vulnerabilities-7-will-shock-you/Exploit, Third Party Advisory
https://www.nagios.com/downloads/nagios-xi/change-log/Release Notes, Vendor Advisory
http://packetstormsecurity.com/files/162783/Nagios-XI-Fusion-Privilege-Escalation-Cross-Site-Scripting-Code-Execution.htmlThird Party Advisory, VDB Entry
https://skylightcyber.com/2021/05/20/13-nagios-vulnerabilities-7-will-shock-you/Exploit, Third Party Advisory
https://www.nagios.com/downloads/nagios-xi/change-log/Release Notes, Vendor Advisory

Timeline

Published: May 24, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-28900?

How severe is CVE-2020-28900?

CVE-2020-28900 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 2.36% probability of exploitation in the next 30 days.

How do I fix CVE-2020-28900?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-28900?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST