CVE-2021-20152Public exploitNetwork attack vector

Unauthenticated file and settings modification via Transmission

Published Dec 30, 2021 · Updated Aug 3, 2024

Authentication bypass in TRENDnet TEW-827DRU 2.08B01 allows remote attackers to modify BitTorrent settings and files over HTTP. When BitTorrent is enabled, the embedded Transmission web client exposes /transmission/web/ on TCP port 9091 without requiring authentication. Any host able to reach that interface can alter download settings and files; the feature must first be enabled.

CVSS severity6.5
Medium
EPSS probability0.82%
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 2.08B01 allows remote attackers to modify BitTorrent settings and files over HTTP. When BitTorrent is enabled, the embedded Transmission web client exposes /transmission/web/ on TCP port 9091 without requiring authentication. Any host able to reach that interface can alter download settings and files; the feature must first be enabled.

The record

CVE
CVE-2021-20152
Published
Dec 30, 2021
Updated
Aug 3, 2024
Vendor
TRENDnet
Product
TEW-827DRU
Classifications
CWE-306, T1190
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-827DRUversion=2.08B01

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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.

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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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1190Exploit Public-Facing Application

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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