How severe is CVE-2020-8187?

CVE-2020-8187 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-2020-8187 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8187?

CVE-2020-8187 primarily affects Citrix Application Delivery Controller Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-8187?

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-2020-8187 published?

CVE-2020-8187 was published on 2020-07-10 and last updated on 2026-06-17.

CVE-2020-8187

CVE-2020-8187 is a high-severity vulnerability in Citrix Application Delivery Controller Firmware 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Citrix Application Delivery Controller Firmware
Published: 2020-07-10
Last modified: 2026-06-17

Description

Improper input validation in Citrix ADC and Citrix Gateway versions before 11.1-63.9 and 12.0-62.10 allows unauthenticated users to perform a denial of service attack.

Frequently asked questions

What is CVE-2020-8187?: Improper input validation in Citrix ADC and Citrix Gateway versions before 11.1-63.9 and 12.0-62.10 allows unauthenticated users to perform a denial of service attack.
How severe is CVE-2020-8187?: CVE-2020-8187 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-2020-8187 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8187?: CVE-2020-8187 primarily affects Citrix Application Delivery Controller Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-8187?: 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-2020-8187 published?: CVE-2020-8187 was published on 2020-07-10 and last updated on 2026-06-17.

References

https://support.citrix.com/article/CTX276688

Affected products (2)

cpe:2.3:o:citrix:application_delivery_controller_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_gateway_firmware:*:*:*:*:*:*:*:*

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