CVE-2021-35973Public exploit

Unauthenticated administrative access via URI substring check

Published Jun 30, 2021 · Updated Aug 4, 2024

Authentication bypass in NETGEAR WAC104 firmware before 1.0.4.15 allows remote attackers to invoke administrative actions over HTTP. mini_httpd checks the raw request URI for the currentsetting.htm substring and sets a flag that skips HTTP Basic Authentication before URL decoding. Network access to the device is sufficient; the bypass permits password changes and can be chained to enable telnetd and obtain an administrative shell.

CVSS severity9.8
Critical
EPSS probability3.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in NETGEAR WAC104 firmware before 1.0.4.15 allows remote attackers to invoke administrative actions over HTTP. mini_httpd checks the raw request URI for the currentsetting.htm substring and sets a flag that skips HTTP Basic Authentication before URL decoding. Network access to the device is sufficient; the bypass permits password changes and can be chained to enable telnetd and obtain an administrative shell.

The record

CVE
CVE-2021-35973
Published
Jun 30, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-697, T1210
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 30, 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 vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8MITRECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.8NETGEARCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-697Incorrect Comparison
T1210Exploitation of Remote Services

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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