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

How to check if you are exposed to CVE-2023-3519

1. Find every Citrix NetScaler ADC and NetScaler Gateway system you or your clients run, including ones exposed to the internet. Those come first: CISA only lists flaws attackers are already using.
2. Compare each version with the fixed versions in the vendor advisory below. Where no fix exists yet, apply the vendor’s mitigation or take the system off the internet.
3. Run a credentialed vulnerability scan to catch the systems you missed, then check that the next scan no longer reports CVE-2023-3519.

US federal agencies had to fix this by 2023-08-09. Everyone else should treat that deadline as a guide: if it has passed, this is overdue.

Timeline

1. 2023-07-19 · Added to CISA's Known Exploited Vulnerabilities catalog
2. 2023-08-09 · Fix-by date for US federal agencies, passed 1,180 days ago

Vendor advisories and fixes

• https://support.citrix.com/article/CTX561482/citrix-adc-and-citrix-gateway-security-bulletin-for-cve20233519-cve20233466-cve20233467

Weakness type

• CWE-94

More exploited Citrix vulnerabilities

CISA lists 27 exploited Citrix vulnerabilities. The closest matches:

• CVE-2026-8452Citrix NetScaler ADC and NetScaler Gateway Improper Restriction of Operations within the Bounds of a Memory Buffer VulnerabilityAdded 2026-08-26
• CVE-2023-6549Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow VulnerabilityAdded 2024-01-17
• CVE-2023-6548Citrix NetScaler ADC and NetScaler Gateway Code Injection VulnerabilityAdded 2024-01-17
• CVE-2023-4966Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow VulnerabilityAdded 2023-10-18
• CVE-2026-88779Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer VulnerabilityAdded 2026-10-04
• CVE-2026-88772Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer VulnerabilityAdded 2026-09-27
• CVE-2026-88771Citrix NetScaler Improper Input Validation VulnerabilityAdded 2026-09-27
• CVE-2026-19490Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel VulnerabilityAdded 2026-09-09

Keep going

• All exploited CVEs
• Check another CVE
• What is CISA KEV?
• What is EPSS?

Sources: CISA Known Exploited Vulnerabilities catalog (version 2026.10.30); EPSS data from FIRST.org; CVSS and descriptions from the NIST National Vulnerability Database. Checked 2026-11-01. This product uses the NVD API but is not endorsed or certified by the NVD.