How severe is CVE-2021-22920?

CVE-2021-22920 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-22920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22920?

CVE-2021-22920 primarily affects Citrix Application Delivery Management. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22920?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-22920 published?

CVE-2021-22920 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-22920

CVE-2021-22920 is a medium-severity vulnerability in Citrix Application Delivery Management with a CVSS 3.x base score of 6.5. 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-284.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Citrix Application Delivery Management
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 a phishing attack through a SAML authentication hijack to steal a valid user session.

Frequently asked questions

What is CVE-2021-22920?: 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 a phishing attack through a SAML authentication hijack to steal a valid user session.
How severe is CVE-2021-22920?: CVE-2021-22920 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-22920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22920?: CVE-2021-22920 primarily affects Citrix Application Delivery Management. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22920?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-22920 published?: CVE-2021-22920 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:a:citrix:application_delivery_management:12.1-62.25:*:*:*:*:*:*:*
cpe:2.3:a:citrix:application_delivery_management:13.0-82.42:*:*:*:*:*:*:*
cpe:2.3:a:citrix:gateway:12.1-62.25:*:*:*:*:*:*:*
cpe:2.3:a:citrix:gateway:13.0-82.42:*:*:*:*:*:*:*

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