CVE-2021-20133: Path Traversal

Published Dec 30, 2021
·
Updated

Quagga Services on D-Link DIR-2640 less than or equal to version 1.11B02 are affected by an absolute path traversal vulnerability that allows a remote, authenticated attacker to set the "message of the day" banner to any file on the system, allowing them to read all or some of the contents of those files. Such sensitive information as hashed credentials, hardcoded plaintext passwords for other services, configuration files, and private keys can be disclosed in this fashion. Improper handling of filenames that identify virtual resources, such as "/dev/urandom" allows an attacker to effect a denial of service attack against the command line interfaces of the Quagga services (zebra and ripd).

Affected Software

2 affected components
Dlink Dir-2640-us Firmware<=1.11b02
Dlink Dir-2640-us

Event History

Dec 30, 2021
CVE Published
via MITRE·09:30 PM
Data Sourced
via MITRE·09:30 PM
DescriptionWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2021-20133?

CVE-2021-20133 has been assessed with a medium severity rating due to its potential for remote exploitation.

2

How do I fix CVE-2021-20133?

To fix CVE-2021-20133, update your D-Link DIR-2640 firmware to a version newer than 1.11B02.

3

Who is affected by CVE-2021-20133?

Users of D-Link DIR-2640 routers running firmware version 1.11B02 or earlier are affected by CVE-2021-20133.

4

What is the impact of CVE-2021-20133?

CVE-2021-20133 allows an authenticated attacker to read arbitrary files from the system through path traversal.

5

Is there a workaround for CVE-2021-20133?

There are no documented workarounds for CVE-2021-20133; the only mitigation is to update to a secure firmware version.

Contact

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