CVE-2021-22919

Name: CVE-2021-22919
Creator: NVD / NIST
Published: 2021-08-05T21:15:10.997+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.94%

Last modified Jun 17, 2026

CVE-2021-22919 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A vulnerability has been discovered in Citrix ADC (formerly known as NetScaler ADC) and Citrix Gateway (formerly known as NetScaler Gateway), and Citrix SD-WAN WANOP Edition models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. These vulnerabilities, if exploited, could lead to the limited available disk space on the appliances being fully consumed.. EPSS estimates a 0.94% chance of exploitation in the next 30 days.

Description

A vulnerability has been discovered in Citrix ADC (formerly known as NetScaler ADC) and Citrix Gateway (formerly known as NetScaler Gateway), and Citrix SD-WAN WANOP Edition models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. These vulnerabilities, if exploited, could lead to the limited available disk space on the appliances being fully consumed.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.94%

56.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Citrix	Application Delivery Controller Firmware	>= 11.1, < 11.1-65.22
Citrix	Application Delivery Controller Firmware	>= 12.1, < 12.1-62.27
Citrix	Application Delivery Controller Firmware	>= 13.0, < 13.0-82.45
Citrix	Application Delivery Controller Firmware	>= 12.1, < 12.1-55.238
Citrix	Gateway	>= 12.1, < 12.1-62.27
Citrix	Gateway	>= 13.0, < 13.0-82.45
Citrix	Netscaler Gateway	>= 11.1, < 11.1-65.22
Citrix	Sd-Wan Wanop	>= 10.2, < 10.2.9.b
Citrix	Sd-Wan Wanop	>= 11.2, < 11.2.3.b
Citrix	Sd-Wan Wanop	>= 11.3, < 11.3.2.a
Citrix	Sd-Wan Wanop	>= 11.4, < 11.4.0.a

References

https://support.citrix.com/article/CTX319135Vendor Advisory
https://support.citrix.com/article/CTX319135Vendor Advisory

Timeline

Published: Aug 5, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-22919?

How severe is CVE-2021-22919?

CVE-2021-22919 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.94% probability of exploitation in the next 30 days.

How do I fix CVE-2021-22919?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-22919?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST