CVE-2021-22956: High severity Citrix Application Delivery Controller Firmware vulnerability

Published Dec 7, 2021
·
Updated

An uncontrolled resource consumption vulnerability exists in Citrix ADC <13.0-83.27, <12.1-63.22 and 11.1-65.23 that could allow an attacker with access to NSIP or SNIP with management interface access to cause a temporary disruption of the Management GUI, Nitro API, and RPC communication.

Affected Software

9 affected components
Citrix Application Delivery Controller Firmware<11.1-65.23
Citrix Application Delivery Controller Firmware>=12.1<12.1-63.22
Citrix Application Delivery Controller Firmware>=13.0<13.0-83.27
Citrix Application Delivery Controller
Citrix Gateway<11.1-65.23
Citrix Gateway>=12.1<12.1-63.22
Citrix Gateway>=13.0<13.0-65.23
Citrix SD-WAN<10.2.9c
Citrix SD-WAN>=11.4.0<11.4.2

Event History

Dec 7, 2021
CVE Published
via MITRE·01:12 PM
Data Sourced
via MITRE·01:12 PM
DescriptionWeakness
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Frequently Asked Questions

1

What is CVE-2021-22956?

CVE-2021-22956 is an uncontrolled resource consumption vulnerability in Citrix ADC <13.0-83.27, <12.1-63.22, and 11.1-65.23 that could allow an attacker to cause a temporary disruption of the Management GUI, Nitro API, and RPC communication.

2

Which software versions are affected by CVE-2021-22956?

CVE-2021-22956 affects Citrix ADC versions <13.0-83.27, <12.1-63.22, and 11.1-65.23.

3

What is the severity of CVE-2021-22956?

CVE-2021-22956 has a severity rating of 7.5 (high).

4

How can an attacker exploit CVE-2021-22956?

An attacker with access to NSIP or SNIP with management interface access can exploit CVE-2021-22956.

5

How can CVE-2021-22956 be mitigated?

Applying the recommended patches from Citrix is the best way to mitigate CVE-2021-22956.

Contact

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