How severe is CVE-2020-8299?

CVE-2020-8299 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-8299 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8299?

CVE-2020-8299 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-2020-8299?

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

When was CVE-2020-8299 published?

CVE-2020-8299 was published on 2021-06-16 and last updated on 2026-06-17.

CVE-2020-8299

CVE-2020-8299 is a medium-severity vulnerability in Citrix Gateway 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-400.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 3.3
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Citrix Gateway
Published: 2021-06-16
Last modified: 2026-06-17

Description

Citrix ADC and Citrix/NetScaler Gateway 13.0 before 13.0-76.29, 12.1-61.18, 11.1-65.20, Citrix ADC 12.1-FIPS before 12.1-55.238, and Citrix SD-WAN WANOP Edition before 11.4.0, 11.3.2, 11.3.1a, 11.2.3a, 11.1.2c, 10.2.9a suffers from uncontrolled resource consumption by way of a network-based denial-of-service from within the same Layer 2 network segment. Note that the attacker must be in the same Layer 2 network segment as the vulnerable appliance.

Frequently asked questions

What is CVE-2020-8299?: Citrix ADC and Citrix/NetScaler Gateway 13.0 before 13.0-76.29, 12.1-61.18, 11.1-65.20, Citrix ADC 12.1-FIPS before 12.1-55.238, and Citrix SD-WAN WANOP Edition before 11.4.0, 11.3.2, 11.3.1a, 11.2.3a, 11.1.2c, 10.2.9a suffers from uncontrolled resource consumption by way of a network-based denial-of-service from within the same Layer 2 network segment. Note that the attacker must be in the same Layer 2 network segment as the vulnerable appliance.
How severe is CVE-2020-8299?: CVE-2020-8299 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-8299 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8299?: CVE-2020-8299 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-2020-8299?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-8299 published?: CVE-2020-8299 was published on 2021-06-16 and last updated on 2026-06-17.

References

https://support.citrix.com/article/CTX297155

Affected products (4)

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

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