CVE-2026-88771CitrixFirewall and VPNSeptember 27, 2026

Citrix NetScaler Improper Input Validation Vulnerability

Critical 9.8Actively exploited

Description

Citrix NetScaler ADC and NetScaler Gateway contain an improper input validation vulnerability that could allow an unauthenticated attacker to execute arbitrary commands.

What to do

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Running Citrix devices? Get an email when a new vulnerability comes out. Free, unsubscribe in one click.
Turn on Citrix alerts

Details

Vendor
Citrix
Product
NetScaler ADC e NetScaler Gateway
CVE
CVE-2026-88771
Affected versions
Citrix NetScaler ADC 14.1: before 14.1-73.37; before 14.1-73.37 FIPS — fixed in 14.1-73.37, 14.1-73.37 FIPS
Citrix NetScaler ADC 13.1: before 13.1-64.23; before 13.1.37.279 FIPS and NDcPP — fixed in 13.1-64.23, 13.1.37.279 FIPS and NDcPP
Citrix NetScaler Gateway 14.1: before 14.1-73.37 — fixed in 14.1-73.37
Citrix NetScaler Gateway 13.1: before 13.1-64.23 — fixed in 13.1-64.23 (from the advisory and NVD; check the exact builds in the official advisory)
CVSS score
9.8
Actively exploited
Yes, listed in the CISA Known Exploited Vulnerabilities catalog
CISA due date
September 30, 2026 (deadline for US federal agencies: a good benchmark for you too)
Source
CISA KEV – original advisory
Published
September 27, 2026

The description and the recommended action are quoted from the public advisory; severity, exploitation status and affected versions are compiled automatically from public sources and may contain errors. The vendor's original advisory prevails: check it before taking action. This information is provided without warranty and does not replace a professional assessment.

More Citrix advisories