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CVE-2026-88771

Status: AnalyzedCritical (9.5)⚠ Active exploitation

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.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

CISA KEV — actively exploited

Affected technologies (2)

Citrix — Netscaler Application Delivery ControllerCitrix — Netscaler Gateway

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2026-88771",
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          "options": [
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          "version": "2.0.3",
          "timestamp": "2026-09-27T00:00:00+00:00"
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          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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              "version": "0",
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          ],
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        },
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          "product": "Gateway",
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  "published": "2026-09-27T17:16:56.260",
  "references": [
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      "tags": [
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    },
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      "tags": [
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      "value": "Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway.\n\nThis 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."
    },
    {
      "lang": "es",
      "value": "Vulnerabilidad de validación de entrada inadecuada en Citrix NetScaler ADC y Citrix NetScaler Gateway.\n\nEste problema afecta a ADC en versiones anteriores a 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS, y 13.1.37.279 FIPS y NDcPP; y a Gateway en versiones anteriores a 14.1-73.37 y 13.1-64.23, lo que permite a un atacante no autenticado ejecutar comandos arbitrarios."
    }
  ],
  "lastModified": "2026-09-29T04:18:01.603",
  "cisaActionDue": "2026-09-30",
  "cisaExploitAdd": "2026-09-27",
  "configurations": [
    {
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  "cisaRequiredAction": "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.",
  "cisaVulnerabilityName": "Citrix NetScaler Improper Input Validation Vulnerability"
}