CVE-2021-4285Network attack vector

Authenticated script execution via unsafe log-name rendering

Published Dec 27, 2022 · Updated Aug 3, 2024

Cross-site scripting in Nagios NCPA before 2.4.0 allows remote authenticated users to execute script through a crafted log name. The Tail Event Logs template reads the name field and passes its value to jQuery html(), causing the browser to parse attacker-controlled markup instead of displaying text. A logged-in user must apply the crafted filter, and the injected script executes in that user's authenticated NCPA GUI origin.

CVSS severity6.1
Medium
EPSS probability1.69%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Nagios NCPA before 2.4.0 allows remote authenticated users to execute script through a crafted log name. The Tail Event Logs template reads the name field and passes its value to jQuery html(), causing the browser to parse attacker-controlled markup instead of displaying text. A logged-in user must apply the crafted filter, and the injected script executes in that user's authenticated NCPA GUI origin.

The record

CVE
CVE-2021-4285
Published
Dec 27, 2022
Updated
Aug 3, 2024
Vendor
Nagios Enterprises, LLC
Product
Nagios Cross-Platform Agent (NCPA)
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 27, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Nagios Enterprises, LLC · Nagios Cross-Platform Agent (NCPA)version=n/a

Published CVSS scores

3.5VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
6.1NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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