CVE-2021-23017

Published May 21, 2021
·
Updated

A flaw was found in nginx. An off-by-one error while processing DNS responses allows a network attacker to write a dot character out of bounds in a heap allocated buffer which can allow overwriting the least significant byte of next heap chunk metadata likely leading to a remote code execution in certain circumstances. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Affected Software

35 affected componentsFixes available
redhat/automation-hub<0:4.2.5-1.el7
0:4.2.5-1.el7
redhat/python-galaxy-ng<0:4.2.5-2.el7
0:4.2.5-2.el7
redhat/python-pulpcore<0:3.7.6-1.el7
0:3.7.6-1.el7
redhat/automation-hub<0:4.2.5-1.el8
0:4.2.5-1.el8
redhat/python-galaxy-ng<0:4.2.5-2.el8
0:4.2.5-2.el8
redhat/python-pulpcore<0:3.7.6-1.el8
0:3.7.6-1.el8
redhat/rh-nginx118-nginx<1:1.18.0-3.el7
1:1.18.0-3.el7
redhat/rh-nginx116-nginx<1:1.16.1-6.el7
1:1.16.1-6.el7
F5 Nginx>=0.6.18<1.20.1
OpenResty OpenResty<1.19.3.2
Fedoraproject Fedora=33
Fedoraproject Fedora=34
NetApp ONTAP Select Deploy administration utility
Oracle Blockchain Platform<21.1.2
Oracle Communications Control Plane Monitor=3.4
Oracle Communications Control Plane Monitor=4.2
Oracle Communications Control Plane Monitor=4.3
Oracle Communications Control Plane Monitor=4.4
Oracle Communications Fraud Monitor>=3.4<=4.4
Oracle Communications Operations Monitor=3.4
Oracle Communications Operations Monitor=4.2
Oracle Communications Operations Monitor=4.3
Oracle Communications Operations Monitor=4.4
Oracle Communications Session Border Controller=8.4
Oracle Communications Session Border Controller=9.0
Oracle Enterprise Communications Broker=3.3.0
Oracle Enterprise Session Border Controller=8.4
Oracle Enterprise Session Border Controller=9.0
Oracle Enterprise Telephony Fraud Monitor=3.4
Oracle Enterprise Telephony Fraud Monitor=4.2
Oracle Enterprise Telephony Fraud Monitor=4.3
Oracle Enterprise Telephony Fraud Monitor=4.4
Oracle GoldenGate<21.4.0.0.0
redhat/nginx<1.21.0
1.21.0
redhat/nginx<1.20.1
1.20.1

Event History

May 25, 2021
CVE Published
12:00 AM
Jun 1, 2021
CVE Published
via MITRE·12:28 PM
Data Sourced
via MITRE·12:28 PM
DescriptionWeakness
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Frequently Asked Questions

1

What is the vulnerability ID for this security issue in nginx resolver?

The vulnerability ID for this security issue in nginx resolver is CVE-2021-23017.

2

What is the severity of CVE-2021-23017?

The severity of CVE-2021-23017 is high with a CVSS score of 8.1.

3

How does the vulnerability in nginx resolver occur?

The vulnerability in nginx resolver is caused by an off-by-one error while processing DNS responses.

4

What is the potential impact of this vulnerability?

The potential impact of this vulnerability is remote code execution.

5

How can I fix the vulnerability in nginx resolver?

To fix the vulnerability in nginx resolver, update to version 1.21.0 or 1.20.1 of nginx.

Contact

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