CVE-2021-42911: Critical severity draytek vigor 2960 firmware vulnerability

Published Mar 29, 2022
·
Updated

A Format String vulnerability exists in DrayTek Vigor 2960 <= 1.5.1.3, DrayTek Vigor 3900 <= 1.5.1.3, and DrayTek Vigor 300B <= 1.5.1.3 in the mainfunction.cgi file via a crafted HTTP message containing malformed QUERY STRING, which could let a remote malicious user execute arbitrary code.

Affected Software

6 affected components
DrayTek Vigor2960 Firmware<=1.5.1.3
DrayTek Vigor2960
DrayTek Vigor3900 Firmware<=1.5.1.3
DrayTek Vigor3900
DrayTek Vigor300b Firmware<=1.5.1.3
DrayTek Vigor300B

Event History

Mar 29, 2022
CVE Published
via MITRE·07:30 PM
Data Sourced
via MITRE·07:30 PM
Description
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Frequently Asked Questions

1

What is CVE-2021-42911?

CVE-2021-42911 is a Format String vulnerability that exists in DrayTek Vigor 2960 <= 1.5.1.3, DrayTek Vigor 3900 <= 1.5.1.3, and DrayTek Vigor 300B <= 1.5.1.3 in the mainfunction.cgi file.

2

How can a remote user exploit CVE-2021-42911?

A remote user can exploit CVE-2021-42911 by sending a crafted HTTP message containing a malformed QUERY STRING, which could allow them to execute arbitrary code.

3

What is the severity of CVE-2021-42911?

CVE-2021-42911 has a severity rating of 9.8 (Critical).

4

Which DrayTek products are affected by CVE-2021-42911?

The DrayTek Vigor 2960 <= 1.5.1.3, DrayTek Vigor 3900 <= 1.5.1.3, and DrayTek Vigor 300B <= 1.5.1.3 are affected by CVE-2021-42911.

5

Is the DrayTek Vigor 2960 vulnerable to CVE-2021-42911?

Yes, the DrayTek Vigor 2960 <= 1.5.1.3 is vulnerable to CVE-2021-42911.

Contact

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