CVE-2021-20150Public exploitNetwork attack vector

Unauthenticated information disclosure via setup-wizard redirect

Published Dec 30, 2021 · Updated Aug 3, 2024

Authentication bypass in TRENDnet TEW-827DRU Firmware 2.08B01 allows remote attackers to read sensitive router data via the setup wizard. The /apply_sec.cgi handler accepts attacker-chosen response-page values in an unauthenticated cancellation request, then redirects to protected administrative pages without enforcing authentication. Network access to the web-management interface is sufficient; published testing found read-only access that exposes configured FTP credentials, system logs, and other administrative data.

CVSS severity5.3
Medium
EPSS probability40.06%
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 TRENDnet TEW-827DRU Firmware 2.08B01 allows remote attackers to read sensitive router data via the setup wizard. The /apply_sec.cgi handler accepts attacker-chosen response-page values in an unauthenticated cancellation request, then redirects to protected administrative pages without enforcing authentication. Network access to the web-management interface is sufficient; published testing found read-only access that exposes configured FTP credentials, system logs, and other administrative data.

The record

CVE
CVE-2021-20150
Published
Dec 30, 2021
Updated
Aug 3, 2024
Vendor
TRENDnet
Product
TEW-827DRU Firmware
Classifications
CWE-306, T1212
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

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

  1. Affected versionversion=2.08B01

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

TRENDnet · TEW-827DRU Firmwareversion=2.08B01

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1212Exploitation for Credential Access

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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