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Vulnerability record · CVE-2021-35479 · published 30 July 2021

CVE-2021-35479: Nagios log server cross-site scripting vulnerability

Nagios · Log Server

Nagios Log Server before 2.1.9 contains Stored XSS in the custom column view for the alert history and audit log function through the affected pp parameter. This affects users who open a crafted link or third-party web page.

5.4 CVSS 3.1 Medium EPSS 13% · top 3.8% CWE-79 · Cross-site scripting
5.4CVSS 3.1 base score, v2 3.5
13%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
6References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

Nagios Log Server before 2.1.9 contains Stored XSS in the custom column view for the alert history and audit log function through the affected pp parameter. This affects users who open a crafted link or third-party web page.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://research.nccgroup.com/2021/07/22/technical-advisory-stored-and-reflected-xss-vulnerability-in-nagios-log-server- ExploitThird Party Advisory
https://research.nccgroup.com/?research=Technical%20advisories Third Party Advisory
https://www.nagios.com/downloads/nagios-log-server/change-log/ Vendor Advisory
https://research.nccgroup.com/2021/07/22/technical-advisory-stored-and-reflected-xss-vulnerability-in-nagios-log-server- ExploitThird Party Advisory
https://research.nccgroup.com/?research=Technical%20advisories Third Party Advisory
https://www.nagios.com/downloads/nagios-log-server/change-log/ Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-35479), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.