CVE-2021-3672: XSS

Published Jul 30, 2021
·
Updated

A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.

Other sources

Missing input validation of host names returned by Domain Name Servers in the c-ares library can lead to output of wrong hostnames (leading to Domain Hijacking).

Red Hat

Affected Software

40 affected componentsFixes available
redhat/c-ares<0:1.13.0-6.el8
0:1.13.0-6.el8
redhat/rh-nodejs14-nodejs<0:14.17.5-1.el7
0:14.17.5-1.el7
redhat/rh-nodejs12-nodejs<0:12.22.5-1.el7
0:12.22.5-1.el7
redhat/rh-nodejs12-nodejs-nodemon<0:2.0.3-5.el7
0:2.0.3-5.el7
redhat/c-ares<1.17.2
1.17.2
C-ares Project C-ares>=1.0.0<1.17.2
Fedoraproject Fedora=33
Fedoraproject Fedora=34
redhat Enterprise Linux=7.0
redhat Enterprise Linux=7.7
redhat Enterprise Linux=8.0
redhat Enterprise Linux Computer Node=1
redhat Enterprise Linux Eus=7.7
redhat Enterprise Linux Eus=8.1
redhat Enterprise Linux Eus=8.2
redhat Enterprise Linux Eus=8.4
redhat Enterprise Linux For Ibm Z Systems=8.0
redhat Enterprise Linux For Ibm Z Systems Eus=8.1
redhat Enterprise Linux For Ibm Z Systems Eus=8.2
redhat Enterprise Linux For Ibm Z Systems Eus=8.4
redhat Enterprise Linux For Power Little Endian=8.0
redhat Enterprise Linux For Power Little Endian Eus=8.1
redhat Enterprise Linux For Power Little Endian Eus=8.2
redhat Enterprise Linux For Power Little Endian Eus=8.4
redhat Enterprise Linux Server Aus=8.2
redhat Enterprise Linux Server Aus=8.4
redhat Enterprise Linux Server Tus=8.2
redhat Enterprise Linux Server Tus=8.4
redhat Enterprise Linux Server Update Services For Sap Solutions=8.1
redhat Enterprise Linux Server Update Services For Sap Solutions=8.2
redhat Enterprise Linux Server Update Services For Sap Solutions=8.4
redhat Enterprise Linux Tus=8.4
redhat Enterprise Linux Workstation=1
Siemens Sinec Infrastructure Network Services<1.0.1.1
Nodejs Node.js>=12.0.0<=12.12.0
Nodejs Node.js>=12.13.0<12.22.5
Nodejs Node.js>=14.0.0<=14.14.0
Nodejs Node.js>=14.15.0<14.17.5
Nodejs Node.js>=16.0.0<16.6.2
PgBouncer PgBouncer<=1.17.0

Event History

Aug 10, 2021
CVE Published
12:00 AM
Nov 23, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-3672?

CVE-2021-3672 is a vulnerability in the c-ares library that allows for potential domain hijacking due to a missing input validation check of host names returned by DNS.

2

What is the severity of CVE-2021-3672?

The severity of CVE-2021-3672 is medium, with a severity score of 5.6.

3

Which software is affected by CVE-2021-3672?

The c-ares library versions up to and excluding 1.17.2 and specific versions of the rh-nodejs14-nodejs, rh-nodejs12-nodejs, and rh-nodejs12-nodejs-nodemon packages are affected.

4

How can I fix the CVE-2021-3672 vulnerability?

To fix the CVE-2021-3672 vulnerability, update the c-ares library to version 1.17.2 or higher.

5

Where can I find more information about CVE-2021-3672?

You can find more information about CVE-2021-3672 in the following references: [Bugzilla: 1992221](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1992221), [Bugzilla: 1992222](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1992222), [c-ares Advisory](https://c-ares.haxx.se/adv_20210810.html).

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