9.8
CRITICAL
CVE-2021-42911
DrayTek Vigor Format String Vulnerability
Description

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.

INFO

Published Date :

March 29, 2022, 8:15 p.m.

Last Modified :

Nov. 21, 2024, 6:28 a.m.

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-42911 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Draytek vigor2960_firmware
2 Draytek vigor300b_firmware
3 Draytek vigor3900_firmware
4 Draytek vigor2960
5 Draytek vigor300b
6 Draytek vigor3900
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-42911.

URL Resource
https://gist.github.com/Cossack9989/e9c1c2d2e69b773ca4251acdd77f2835 Exploit Third Party Advisory
https://gist.github.com/Cossack9989/e9c1c2d2e69b773ca4251acdd77f2835 Exploit Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-42911 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-42911 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://gist.github.com/Cossack9989/e9c1c2d2e69b773ca4251acdd77f2835
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Apr. 05, 2022

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://gist.github.com/Cossack9989/e9c1c2d2e69b773ca4251acdd77f2835 No Types Assigned https://gist.github.com/Cossack9989/e9c1c2d2e69b773ca4251acdd77f2835 Exploit, Third Party Advisory
    Added CWE NIST CWE-134
    Added CPE Configuration AND OR *cpe:2.3:o:draytek:vigor2960_firmware:*:*:*:*:*:*:*:* versions up to (including) 1.5.1.3 OR cpe:2.3:h:draytek:vigor2960:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:draytek:vigor3900_firmware:*:*:*:*:*:*:*:* versions up to (including) 1.5.1.3 OR cpe:2.3:h:draytek:vigor3900:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:draytek:vigor300b_firmware:*:*:*:*:*:*:*:* versions up to (including) 1.5.1.3 OR cpe:2.3:h:draytek:vigor300b:-:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-42911 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-42911 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.67 }} -0.21%

score

0.79676

percentile

CVSS31 - Vulnerability Scoring System
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