CVE-2021-20155Public exploitNetwork attack vector

Configuration tampering via fixed backup encryption password

Published Dec 30, 2021 · Updated Aug 3, 2024

Hard-coded credentials in TRENDnet TEW-827DRU 2.08B01 allow remote authenticated users to alter protected router settings. The management interface encrypts exported configuration backups with the fixed password 12345678, then accepts modified and re-encrypted files for restoration. Access to configuration backup and restore is required; arbitrary code execution is reported only when chained with other flaws.

CVSS severity9.8
Critical
EPSS probability1.90%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Hard-coded credentials in TRENDnet TEW-827DRU 2.08B01 allow remote authenticated users to alter protected router settings. The management interface encrypts exported configuration backups with the fixed password 12345678, then accepts modified and re-encrypted files for restoration. Access to configuration backup and restore is required; arbitrary code execution is reported only when chained with other flaws.

The record

CVE
CVE-2021-20155
Published
Dec 30, 2021
Updated
Aug 3, 2024
Vendor
TRENDnet
Product
TEW-827DRU
Classifications
CWE-798, T1565.001
Attack vector
network
Privileges
authenticated

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 privilegesauthenticated

What is affected?

TRENDnet · TEW-827DRUversion=2.08B01

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/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

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials
T1565.001Stored Data Manipulation

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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