CVE-2021-38535

Stored script execution via undisclosed input handling

Published Aug 10, 2021 · Updated Aug 4, 2024

Stored cross-site scripting in NETGEAR router and gateway firmware allows remote authenticated users to execute script in an administrator's browser. NETGEAR has not published the affected management-interface field, storage path, or missing output-encoding operation. Exploitation requires adjacent-network access, high privileges, and an administrator to view the stored content; successful script execution can read or alter browser-accessible management data.

CVSS severity4.8
Medium
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in NETGEAR router and gateway firmware allows remote authenticated users to execute script in an administrator's browser. NETGEAR has not published the affected management-interface field, storage path, or missing output-encoding operation. Exploitation requires adjacent-network access, high privileges, and an administrator to view the stored content; successful script execution can read or alter browser-accessible management data.

The record

CVE
CVE-2021-38535
Published
Aug 10, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1203
Attack vector
adjacent
Privileges
admin

Timeline

How it unfolded

  1. Aug 10, 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 privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
4.3MITRECVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
4.3NETGEARCVSS:3.0/AV:A/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/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)
Vectoradjacent
Privilegesadmin
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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