# CVE-2023-3519: Netscaler Gateway - RCE

> Live exploitation tracking for CVE-2023-3519 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2023-3519

## Key facts

- **Exploitation phase:** Background Noise. Continuous low-level scanning or exploitation attempts are observed, mostly opportunistic and automated.
- **CVSS score:** 9.8
- **Public exploit available:** Yes
- **Affected products:** Citrix Netscaler Gateway
- **Weaknesses:** CWE-94 (Improper Control of Generation of Code ('Code Injection'))
- **Tags:** sslvpn

## Description

Unauthenticated remote code execution

## CrowdSec analysis

[CVE-2023-3519](https://euvd.enisa.europa.eu/vulnerability/CVE-2023-3519) is a critical vulnerability that allows unauthenticated remote code execution.

CrowdSec has been tracking this vulnerability and its exploits since 15th of December 2023.

Insights from the CrowdSec network reveal that the attackers trying to exploit CVE-2023-3519 are composed of a fairly even mix of opportunistic and targeted actors. Some attackers employ preliminary reconnaissance, while others use indiscriminate scanning.
CrowdSec network telemetry also shows that exploitation of CVE-2023-3519 has significantly declined over the past week. Attack volumes are well below the long-term average, suggesting attackers are rapidly losing interest. The vulnerability appears to be falling out of active use across most threat landscapes.

Exploitation attempts are concentrated on URLs containing `/saml/login`.

## Timeline

- 2023-07-19: CVE Published. CVE-2023-3519 is published to NVD.
- 2023-07-19: CISA KEV. CVE-2023-3519 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2023-08-09: CISA Remediation Deadline. Expiration of the CISA remediation deadline as described in [BOD 22-01](https://www.cisa.gov/news-events/directives/bod-22-01-reducing-significant-risk-known-exploited-vulnerabilities).
- 2023-12-15: Rule Released. CrowdSec releases a rule to detect CVE-2023-3519 exploitation attempts against the CrowdSec Network.
- 2025-04-01: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2023-3519 for the first time.

## References

- https://www.zscaler.com/fr/blogs/security-research/security-advisory-remote-code-execution-vulnerability-cve-2023-3519
- https://support.citrix.com/external/article?articleUrl=CTX561482-citrix-adc-and-citrix-gateway-security-bulletin-for-cve20233519-cve20233466-cve20233467&language=en_US

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2023-3519) follows observed exploitation activity for CVE-2023-3519. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.