CVE-2026-84409Network attack vector

Administrative code execution via update-metadata HTML injection

Published Sep 29, 2026 · Updated Sep 29, 2026

Stored cross-site scripting in Lantronix G520 Series firmware before 2.6.0.7R6 allows context-dependent attackers to run script in the admin UI. The update mechanism stores metadata fetched over HTTP, and the update-information page inserts the stored value as HTML without treating it as text. An attacker must influence the update metadata and have an administrator view that page; script running in the authenticated origin can reach an interface that executes system commands as root.

CVSS severityUnavailable
Unscored
EPSS probability0.39%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Lantronix G520 Series firmware before 2.6.0.7R6 allows context-dependent attackers to run script in the admin UI. The update mechanism stores metadata fetched over HTTP, and the update-information page inserts the stored value as HTML without treating it as text. An attacker must influence the update metadata and have an administrator view that page; script running in the authenticated origin can reach an interface that executes system commands as root.

The record

CVE
CVE-2026-84409
Published
Sep 29, 2026
Updated
Sep 29, 2026
Vendor
Lantronix
Product
G520 Series
Classifications
T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 29, 2026Record 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=2.6.0.4R6 stable

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Lantronix · G520 Seriesversion=2.6.0.4R6 stable

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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