CVE-2023-3519: Citrix NetScaler ADC · Code Injection
Affects Citrix NetScaler ADCSource CVE Database V5
Exploited in the wild · used in ransomware campaigns · KEV due 9 Aug 2023 · public exploit available (Metasploit) · 99% EPSS : apply the vendor's fix or mitigations to Citrix NetScaler ADC now.
Data as of 26 Oct 2026, 06:26 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else.
- Ransomware
- Used in ransomware campaigns
- EPSS
- 99.7% chance of exploitation in 30 days – higher than 99% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 19 Jul 2023
Detectable: evidence found.
nuclei template: Citrix NetScaler ADC and NetScaler Gateway - Remote Code Execution
Weaponised: evidence found.
Exploited in the wildExploited: evidence found.
Listed in CISA KEV the same day as disclosure
Observed by OffSeq MirageSeen by Mirage: evidence found.
21 honeypot hits, first 3.3 years after disclosure
Timeline
CVE ID reserved
by Citrix
, 14 days before disclosure
CVE published
on cve.org
, t = 0
Added to CISA KEV (opens in a new tab)
exploitation confirmed · ransomware use known
, the same day as disclosure
KEV remediation due
US federal deadline
, 21 days after disclosure
First seen by OffSeq Mirage
from 4 attacker networks; activity in United Kingdom, Belgium, United States
, 3.3 years after disclosure
Last seen by OffSeq Mirage (opens in a new tab)
25 Oct 2026, 20:24 UTC
, 3.3 years after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), OffSeq Mirage (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Citrix NetScaler ADC | Affected
| Fixed in– |
Check the firmware or software version for Citrix NetScaler ADC in the device's admin interface against the vendor advisory.
Description
CVE-2023-3519 is a critical unauthenticated remote code execution vulnerability in Citrix NetScaler ADC. It involves improper control of code generation (CWE-94), allowing attackers to execute arbitrary code without authentication. The vulnerability affects specific versions of NetScaler ADC, including 13.0, 13.1, 13.1-FIPS, 12.1-FIPS, and 12.1-NDcPP. It has a CVSS score of 9.8, indicating a severe impact on confidentiality, integrity, and availability. Exploits are known in the wild, and the vulnerability has been used in ransomware campaigns. No patch links are provided in the data, and the product is not a cloud service.
References
- support.citrix.com/article/CTX561482/citrix-adc-and-citrix-gateway-security-bulletin-for-cve20233519-cve20233466-cve20233467 (opens in a new tab)
- packetstormsecurity.com/files/173997/Citrix-ADC-NetScaler-Remote-Code-Execution.html (opens in a new tab)
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-3519 (opens in a new tab)