CVE-2026-84189Public exploitNetwork attack vectorHinoki check available

Stored XSS via unescaped Oxidized response fields

Published Sep 1, 2026 · Updated Sep 1, 2026

Stored XSS in LibreNMS before 26.7.0 allows remote authenticated users to execute script in showconfig viewers' browsers. The showconfig page concatenates Oxidized JSON name, IP, model, author, and commit-message values into HTML without htmlspecialchars(). Exploitation requires an administrator to enable Oxidized and point its URL at an attacker-controlled server, after which viewing any device's showconfig tab triggers the script.

CVSS severity8.1
High
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stored XSS in LibreNMS before 26.7.0 allows remote authenticated users to execute script in showconfig viewers' browsers. The showconfig page concatenates Oxidized JSON name, IP, model, author, and commit-message values into HTML without htmlspecialchars(). Exploitation requires an administrator to enable Oxidized and point its URL at an attacker-controlled server, after which viewing any device's showconfig tab triggers the script.

The record

CVE
CVE-2026-84189
Published
Sep 1, 2026
Updated
Sep 1, 2026
Vendor
LibreNMS
Product
LibreNMS
Classifications
CWE-918, CWE-79, T1059.007
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Sep 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <26.7.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

LibreNMS · LibreNMSversion=0 <26.7.0

Published CVSS scores

9.2VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N
8.1GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

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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