---
id: "CVE-2019-19781"
kind: "vulnerability"
aliases: ["CVE-2019-19781"]
title: "Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance: Citrix ADC, Gateway, and SD-WAN WANOP Appliance Code Execution Vulnerability"
severity: "critical"
cvss: 9.8
epss: 0.99999
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["citrix", "citrix-adc", "citrix-gateway", "exploited", "infrastructure", "ransomware", "sd-wan-wanop", "self-hosted"]
not_affected_if: ["unaffected-model-or-build"]
published_at: "2019-12-27T14:15:12+00:00"
first_seen_at: "2026-10-23T19:11:53+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2019-19781", "first_seen_at": "2026-10-23T19:11:53+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2019-19781", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-19781", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance: Citrix ADC, Gateway, and SD-WAN WANOP Appliance Code Execution Vulnerability

Citrix ADC, Citrix Gateway, and Citrix SD-WAN WANOP appliances contain an unspecified flaw that lets an unauthenticated attacker run code on the device. CISA lists it as actively exploited in the wild and tied to ransomware campaigns.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance affected ? fixed ?

## How to check

Check the appliance firmware or build version against the Citrix advisory for CVE-2019-19781; the sources do not give a version command.

## Fix

Apply the Citrix vendor update for the affected ADC, Gateway, or SD-WAN WANOP build (CISA: 'Apply updates per vendor instructions'); specific fixed versions are not in the sources.

## Timeline

- 2026-10-23T19:11:53+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2019-19781
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2019-19781
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2019-19781

## From the sources

Citrix ADC, Citrix Gateway, and multiple Citrix SD-WAN WANOP appliance models contain an unspecified vulnerability that could allow an unauthenticated attacker to perform code execution.

CISA required action: Apply updates per vendor instructions.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_