Medium severity · published Oct 30, 2025
CVE-2021-47699
Nagios XI versions prior to 5.8.7 are vulnerable to cross-site scripting (XSS) via the Audit Log page’s Send to NLS form
5.4
CVSS
0.4%
EPSS
No
On KEV
Description
Nagios XI versions prior to 5.8.7 are vulnerable to cross-site scripting (XSS) via the Audit Log page’s Send to NLS form. Insufficient validation or escaping of user-supplied input may allow an attacker to inject and execute arbitrary script in the context of a victim's browser.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NX
Nagios XI · Nagios
before 5.8.7 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-47699
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-47699
Release Notes
https://www.nagios.com/changelog/nagios-xi/
Third Party Advisory
https://www.vulncheck.com/advisories/nagios-xi-xss-in-audit-log-via-send-to-nls-form
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