Citrix · NetScaler ADC and NetScaler Gateway
CVE-2023-3519
Citrix NetScaler ADC and NetScaler Gateway Code Injection Vulnerability
Exploited in attacks
Used by ransomware
Critical 9.8 Attack chance: 99.7%
What it is
Unauthenticated remote code execution
CISA: Citrix NetScaler ADC and NetScaler Gateway contains a code injection vulnerability that allows for unauthenticated remote code execution.
What to do
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Deadline for US federal agencies: August 9, 2023
More exploited flaws from Citrix
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Aug 26, 2026 | Improper Restriction of Operations within the Bounds of a Memory Buffer | NetScaler ADC and NetScaler Gateway | High 8.8 | 1.0% |
| Jan 17, 2024 | Code Injection | NetScaler ADC and NetScaler Gateway | Medium 5.5 | 3.2% |
| Jan 17, 2024 | Buffer Overflow | NetScaler ADC and NetScaler Gateway | High 8.2 | 58% |
| Oct 18, 2023 | Buffer Overflow | NetScaler ADC and NetScaler Gateway | Critical 9.4 | >99.9% |
| Oct 4, 2026 | Improper Restriction of Operations within the Bounds of a Memory Buffer | NetScaler | High 8.7 | 11% |
| Sep 27, 2026 | Improper Input Validation | NetScaler | Critical 9.5 | 82% |
| Sep 27, 2026 | Improper Restriction of Operations within the Bounds of a Memory Buffer | NetScaler | Critical 9.5 | 78% |
| Sep 9, 2026 | Authentication Bypass Using an Alternate Path or Channel | NetScaler | Critical 9.3 | 33% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.