CVE-2021-38156Public exploitNetwork attack vector

Administrator-session script execution via unencoded dashboard titles

Published Sep 15, 2021 · Updated Aug 4, 2024

Stored XSS in Nagios XI before 5.8.6 allows remote authenticated users to execute JavaScript when an administrator edits a dashboard. The dashboard-title editor loads a stored name as unencoded HTML, so injected script elements execute in the administrator's browser. Exploitation requires dashboard-name write access and an administrator to open the edit interface; the script runs in the administrator's Nagios XI web session.

CVSS severity5.4
Medium
EPSS probability88.94%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Nagios XI before 5.8.6 allows remote authenticated users to execute JavaScript when an administrator edits a dashboard. The dashboard-title editor loads a stored name as unencoded HTML, so injected script elements execute in the administrator's browser. Exploitation requires dashboard-name write access and an administrator to open the edit interface; the script runs in the administrator's Nagios XI web session.

The record

CVE
CVE-2021-38156
Published
Sep 15, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/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 exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

Public exploit references

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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