Improper input validation in Citrix ADC
Priority CRITICAL 100Exploited in the wildCWE-20Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
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.
Why it matters now
Exploitation Active In CISA KEV since 2026-09-27CISA due date 2026-09-30
EPSS 0.81894 99th percentileScored 2026-11-07
Fix Fixed ADC (Citrix NetScaler): 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS +1Gateway (Citrix NetScaler): 14.1-73.37, 13.1-64.23
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Active
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Citrix | ADC | before 14.1-73.37; before 13.1-64.23; before 14.1-73.37 FIPS; before 13.1.37.279 FIPS and NDcPP | 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS, 13.1.37.279 FIPS and NDcPP | Patch available | CNA |
| Citrix | Gateway | before 14.1-73.37; before 13.1-64.23 | 14.1-73.37, 13.1-64.23 | Patch available | CNA |
- ADC VendorCitrix Affected before 14.1-73.37; before 13.1-64.23; before 14.1-73.37 FIPS; before 13.1.37.279 FIPS and NDcPP Fixed in 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS, 13.1.37.279 FIPS and NDcPP Patch available CNA
- Gateway VendorCitrix Affected before 14.1-73.37; before 13.1-64.23 Fixed in 14.1-73.37, 13.1-64.23 Patch available CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* | 13.1 to before 13.1-64.23 | Vulnerable | Citrix |
| cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* | 13.1 to before 13.1.37.279 | Vulnerable | Citrix |
| cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:* | 13.1 to before 13.1.37.279 | Vulnerable | Citrix |
| cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* | 14.1 to before 14.1-73.37 | Vulnerable | Citrix |
| cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* | 14.1-66.68 – 14.1-73.37 | Vulnerable | Citrix |
| cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* | 13.1 to before 13.1-64.23; 14.1 to before 14.1-73.37 | Vulnerable | Citrix |
- cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* Versions 13.1 to before 13.1-64.23 Vulnerable ·Citrix
- cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* Versions 13.1 to before 13.1.37.279 Vulnerable ·Citrix
- cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:* Versions 13.1 to before 13.1.37.279 Vulnerable ·Citrix
- cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* Versions 14.1 to before 14.1-73.37 Vulnerable ·Citrix
- cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* Versions 14.1-66.68 – 14.1-73.37 Vulnerable ·Citrix
- cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* Versions 13.1 to before 13.1-64.23; 14.1 to before 14.1-73.37 Vulnerable ·Citrix
Remediation
- Fix · CNA ADC (Citrix NetScaler) Fixed in 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS, 13.1.37.279 FIPS and NDcPP
- Fix · CNA Gateway (Citrix NetScaler) Fixed in 14.1-73.37, 13.1-64.23
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Citrix NetScaler ADC, Gateway 13.1-64.23, 13.1.37.279 FIPS and NDcPP and 2 more versions
7 records Highest priority Priority CRITICAL 2 CRITICAL, 4 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2026-60195 Memory overflow vulnerability leading to Remote Code Execution or Denial of ServicePriority CRITICAL 100
- TI-2026-60201 TCP Initial Sequence Number (ISN) predictionPriority MEDIUM 47
- TI-2026-60199 Memory overflow vulnerability leading to unpredictable or erroneous behavior or Denial of ServicePriority MEDIUM 46
Timeline
- 2026-09-27 Added to CISA KEV
- 2026-10-02 Threatist record created from CVE-2026-88771
- 2026-10-03 Alias added: GHSA-mx58-p288-86qp
- 2026-10-23 EPSS moved to the 90th–95th percentile
- 2026-10-25 EPSS moved to the 99th percentile and above
References
More Citrix Netscaler Application Delivery Controller vulnerabilities
- TI-2026-60195 Memory overflow vulnerability leading to Remote Code Execution or Denial of Service KEVCVSS 4.0CRITICAL 9.5
- TI-2023-04571 Unauthenticated sensitive information disclosure in Citrix NetScaler ADC KEVCVSS 3.1CRITICAL 9.4
- TI-2023-03284 Unauthenticated remote code execution in Citrix NetScaler ADC KEVCVSS 3.1CRITICAL 9.8
- TI-2026-15872 NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-19490 KEVCVSS 4.0CRITICAL 9.3
- TI-2026-02639 Insufficient input validation leading to memory overread KEVCVSS 4.0CRITICAL 9.3
- TI-2025-07100 Memory corruption in Citrix ADC KEVCVSS 4.0CRITICAL 9.2
Sources
- CVE-2026-88771 · CVE Program
- CVE-2026-88771 · NVD
- CISA Known Exploited Vulnerabilities
- FIRST EPSS
- GHSA-mx58-p288-86qp · GitHub Advisory Database · CC BY 4.0
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