CVE-2021-45673

Stored script execution via undisclosed router input

Published Dec 26, 2021 · Updated Aug 4, 2024

Stored XSS in affected NETGEAR router firmware allows remote authenticated users to run script in another user's browser. NETGEAR has not disclosed the affected input, storage path, or rendering locus within the router management interface. Exploitation requires adjacent-network access, low privileges, and user interaction; the script can read or modify browser-accessible data.

CVSS severity5.4
Medium
EPSS probability0.48%
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 affected NETGEAR router firmware allows remote authenticated users to run script in another user's browser. NETGEAR has not disclosed the affected input, storage path, or rendering locus within the router management interface. Exploitation requires adjacent-network access, low privileges, and user interaction; the script can read or modify browser-accessible data.

The record

CVE
CVE-2021-45673
Published
Dec 26, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1059.007
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 26, 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

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

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.5NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
4.8MITRECVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
5.4NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
4.8NETGEARCVSS:3.0/AV:A/AC:L/PR:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

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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