How severe is CVE-2026-88771?

CVE-2026-88771 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-2026-88771 being actively exploited?

Yes. CVE-2026-88771 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-09-27, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-88771?

CVE-2026-88771 primarily affects Citrix Netscaler Application Delivery Controller. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-88771?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

When was CVE-2026-88771 published?

CVE-2026-88771 was published on 2026-09-27 and last updated on 2026-09-29.

CVE-2026-88771

CVE-2026-88771 is a critical-severity vulnerability in Citrix Netscaler Application Delivery Controller with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-09-27). The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 9.5
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-09-27)
Weakness: CWE-20
Affected product: Citrix Netscaler Application Delivery Controller
Published: 2026-09-27
Last modified: 2026-09-29

Description

Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to an unauthenticated attacker to execute arbitrary commands.

Frequently asked questions

What is CVE-2026-88771?: Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to an unauthenticated attacker to execute arbitrary commands.
How severe is CVE-2026-88771?: CVE-2026-88771 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-2026-88771 being actively exploited?: Yes. CVE-2026-88771 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-09-27, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-88771?: CVE-2026-88771 primarily affects Citrix Netscaler Application Delivery Controller. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-88771?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
When was CVE-2026-88771 published?: CVE-2026-88771 was published on 2026-09-27 and last updated on 2026-09-29.

References

Affected products (4)

cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:*
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:*
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:*
cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:*

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