How severe is CVE-2021-22919?

CVE-2021-22919 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-22919 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22919?

CVE-2021-22919 primarily affects Citrix Gateway. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22919?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-22919 published?

CVE-2021-22919 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-22919

CVE-2021-22919 is a high-severity vulnerability in Citrix Gateway with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Citrix Gateway
Published: 2021-08-05
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-22919?: 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.
How severe is CVE-2021-22919?: CVE-2021-22919 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-22919 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22919?: CVE-2021-22919 primarily affects Citrix Gateway. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22919?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-22919 published?: CVE-2021-22919 was published on 2021-08-05 and last updated on 2026-06-17.

References

https://support.citrix.com/article/CTX319135

Affected products (4)

cpe:2.3:o:citrix:application_delivery_controller_firmware:*:*:*:*:*:*:*:*
cpe:2.3:a:citrix:gateway:*:*:*:*:*:*:*:*
cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:*
cpe:2.3:o:citrix:sd-wan_wanop:*:*:*:*:*:*:*:*

More vulnerabilities in Citrix Gateway

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