How severe is CVE-2018-6809?

CVE-2018-6809 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-6809 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6809?

CVE-2018-6809 primarily affects Citrix Netscaler Application Delivery Controller Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-6809?

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

When was CVE-2018-6809 published?

CVE-2018-6809 was published on 2018-03-06 and last updated on 2026-06-17.

CVE-2018-6809

CVE-2018-6809 is a critical-severity vulnerability in Citrix Netscaler Application Delivery Controller Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Citrix Netscaler Application Delivery Controller Firmware
Published: 2018-03-06
Last modified: 2026-06-17

Description

NetScaler ADC 10.5, 11.0, 11.1, and 12.0, and NetScaler Gateway 10.5, 11.0, 11.1, and 12.0 allow remote attackers to gain privilege on a target system.

Frequently asked questions

What is CVE-2018-6809?: NetScaler ADC 10.5, 11.0, 11.1, and 12.0, and NetScaler Gateway 10.5, 11.0, 11.1, and 12.0 allow remote attackers to gain privilege on a target system.
How severe is CVE-2018-6809?: CVE-2018-6809 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-6809 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6809?: CVE-2018-6809 primarily affects Citrix Netscaler Application Delivery Controller Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-6809?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-6809 published?: CVE-2018-6809 was published on 2018-03-06 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:o:citrix:netscaler_application_delivery_controller_firmware:10.5:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_application_delivery_controller_firmware:11.0:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_application_delivery_controller_firmware:11.1:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_application_delivery_controller_firmware:12.0:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_gateway_firmware:10.5:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_gateway_firmware:11.0:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_gateway_firmware:11.1:*:*:*:*:*:*:*
cpe:2.3:o:citrix:netscaler_gateway_firmware:12.0:*:*:*:*:*:*:*

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