---
id: "CVE-2023-3519"
kind: "vulnerability"
aliases: ["CVE-2023-3519"]
title: "Unauthenticated remote code execution"
severity: "critical"
cvss: 9.8
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Citrix NetScaler ADC and NetScaler Gateway", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "citrix netscaler application delivery controller", "fixed": ["12.1-55.297"], "affected": ">= 12.1, < 12.1-55.297", "ecosystem": "vendor"}, {"name": "citrix netscaler application delivery controller", "fixed": ["13.0-91.13"], "affected": ">= 13.0, < 13.0-91.13", "ecosystem": "vendor"}, {"name": "citrix netscaler application delivery controller", "fixed": ["13.1-37.159"], "affected": ">= 13.1, < 13.1-37.159", "ecosystem": "vendor"}, {"name": "citrix netscaler application delivery controller", "fixed": ["13.1-49.13"], "affected": ">= 13.1, < 13.1-49.13", "ecosystem": "vendor"}, {"name": "citrix netscaler gateway", "fixed": ["13.0-91.13"], "affected": ">= 13.0, < 13.0-91.13", "ecosystem": "vendor"}, {"name": "citrix netscaler gateway", "fixed": ["13.1-49.13"], "affected": ">= 13.1, < 13.1-49.13", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["citrix", "exploited", "gateway", "infrastructure", "netscaler", "ransomware", "self-hosted"]
not_affected_if: ["managed-hosting"]
published_at: "2023-07-19T00:00:00+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T22:29:04+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-3519", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-3519", "first_seen_at": "2026-10-23T22:29:04+00:00"}]
---

# Unauthenticated remote code execution

Citrix NetScaler ADC and NetScaler Gateway contain a code injection flaw that lets an unauthenticated remote attacker run code on the appliance. CISA lists it as actively exploited, with ransomware use noted in the catalog.

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

## Affected

- vendor:Citrix NetScaler ADC and NetScaler Gateway affected ? fixed ?
- vendor:citrix netscaler application delivery controller affected >= 12.1, < 12.1-55.297 fixed 12.1-55.297
- vendor:citrix netscaler application delivery controller affected >= 13.0, < 13.0-91.13 fixed 13.0-91.13
- vendor:citrix netscaler application delivery controller affected >= 13.1, < 13.1-37.159 fixed 13.1-37.159
- vendor:citrix netscaler application delivery controller affected >= 13.1, < 13.1-49.13 fixed 13.1-49.13
- vendor:citrix netscaler gateway affected >= 13.0, < 13.0-91.13 fixed 13.0-91.13
- vendor:citrix netscaler gateway affected >= 13.1, < 13.1-49.13 fixed 13.1-49.13

## Fix

Apply the mitigations or fixed build per Citrix vendor instructions; the sources do not name the versions.
If no mitigation is available, discontinue use of the product per CISA guidance.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-3519
- 2026-10-23T22:29:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2023-3519

## From the sources

Citrix NetScaler ADC and NetScaler Gateway contains a code injection vulnerability that allows for unauthenticated remote code execution.

CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

---

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