# CVE-2023-3519: Citrix NetScaler ADC and NetScaler Gateway Code Injection


- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 19 Jul 2023 (CISA KEV), used in ransomware
- **Fix available:** No
- **Published:** 19 Jul 2023
- **Updated:** 5 Aug 2026
- **Also known as:** GHSA-m4j4-rmj5-w5gp

## What is CVE-2023-3519?

CVE-2023-3519 is a critical vulnerability in Citrix NetScaler ADC, published on 19 Jul 2023. 

### Official description

Unauthenticated remote code execution

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2023-3519?

It affects 2 products.


Products: Citrix NetScaler ADC, Citrix Netscaler Gateway.

## How do I fix CVE-2023-3519?

No fix has been published for CVE-2023-3519 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 9 Aug 2023.

## Is CVE-2023-3519 being exploited?

Yes. Attackers have exploited CVE-2023-3519 in the wild since at least 19 Jul 2023, including in ransomware campaigns.

Public exploit code:

- RCE exploit for CVE-2023-3519 (github_poc): https://github.com/BishopFox/CVE-2023-3519
- Passively fingerprint Citrix ADC / NetScaler ADC & Gateway builds and detect known CVEs — CVE-2023-3519, CitrixBleed 2/3, CVE-2026-8452, and CVE-2026-88771/88772 (KEV) (github_poc): https://github.com/securekomodo/citrixInspector
- https://github.com/mandiant/citrix-ioc-scanner-cve-2023-3519 (github_poc): https://github.com/mandiant/citrix-ioc-scanner-cve-2023-3519
- Citrix Scanner for CVE-2023-3519 (github_poc): https://github.com/telekom-security/cve-2023-3519-citrix-scanner
- https://github.com/mr-r3b00t/CVE-2023-3519 (github_poc): https://github.com/mr-r3b00t/CVE-2023-3519
- CVE-2023-3519 vuln for nuclei scanner (github_poc): https://github.com/SalehLardhi/CVE-2023-3519

## Other vulnerabilities in Citrix NetScaler ADC

- [CVE-2026-88771](https://insights.sbomify.com/CVE-2026-88771/): Citrix NetScaler Improper Input Validation (critical 9.5, exploited in the wild)
- [CVE-2026-88772](https://insights.sbomify.com/CVE-2026-88772/): Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer (critical 9.5, exploited in the wild)
- [CVE-2023-4966](https://insights.sbomify.com/CVE-2023-4966/): Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow (critical 9.4, exploited in the wild)
- [CVE-2026-19490](https://insights.sbomify.com/CVE-2026-19490/): Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel (critical 9.3, exploited in the wild)
- [CVE-2026-3055](https://insights.sbomify.com/CVE-2026-3055/): Citrix NetScaler Out-of-Bounds Read (critical 9.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-3519 and fix it if it is affected.

What it is: CVE-2023-3519 is a critical vulnerability in Citrix NetScaler ADC, published on 19 Jul 2023. 
Exploitation: Yes. Attackers have exploited CVE-2023-3519 in the wild since at least 19 Jul 2023, including in ransomware campaigns.

Affected product: Citrix NetScaler ADC. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-3519/ (Markdown: https://insights.sbomify.com/CVE-2023-3519/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-3519
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-3519
- OSV: https://osv.dev/vulnerability/CVE-2023-3519

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-3519/
Summaries are generated and may contain mistakes; the official description above is the record.