CVE-2021-25299

Name: CVE-2021-25299
Creator: NVD / NIST
Published: 2021-02-15T13:15:12.92+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 96.86%

Last modified Jun 17, 2026

CVE-2021-25299 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. Nagios XI version xi-5.7.5 is affected by cross-site scripting (XSS). The vulnerability exists in the file /usr/local/nagiosxi/html/admin/sshterm.php due to improper sanitization of user-controlled input. EPSS estimates a 96.86% chance of exploitation in the next 30 days.

Description

Nagios XI version xi-5.7.5 is affected by cross-site scripting (XSS). The vulnerability exists in the file /usr/local/nagiosxi/html/admin/sshterm.php due to improper sanitization of user-controlled input. A maliciously crafted URL, when clicked by an admin user, can be used to steal his/her session cookies or it can be chained with the previous bugs to get one-click remote command execution (RCE) on the Nagios XI server.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

96.86%

99.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Nagios	Nagios Xi	5.7.5

References

http://nagios.comProduct
http://packetstormsecurity.com/files/161561/Nagios-XI-5.7.5-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
https://assets.nagios.com/downloads/nagiosxi/versions.phpProduct
https://github.com/fs0c-sh/nagios-xi-5.7.5-bugs/blob/main/README.mdExploit, Third Party Advisory
http://nagios.comProduct
http://packetstormsecurity.com/files/161561/Nagios-XI-5.7.5-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
https://assets.nagios.com/downloads/nagiosxi/versions.phpProduct
https://github.com/fs0c-sh/nagios-xi-5.7.5-bugs/blob/main/README.mdExploit, Third Party Advisory

Timeline

Published: Feb 15, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-25299?

How severe is CVE-2021-25299?

CVE-2021-25299 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 96.86% probability of exploitation in the next 30 days.

How do I fix CVE-2021-25299?

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-2021-25299?

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

Scan your code now

Source: NVD / NIST