Assessment
Why it matters
CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 100.0%; technical severity is CVSS 7.5.
Sensitive information disclosure in NetScaler ADC and NetScaler Gateway when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server.
Who should care
- Teams operating NetScaler ADC and NetScaler Gateway, Netscaler Application Delivery Controller, Netscaler Gateway
- Vulnerability and exposure management teams
- Security operations teams monitoring exploitation activity
Response plan
What I would do
- Confirm whether NetScaler ADC and NetScaler Gateway, Netscaler Application Delivery Controller, Netscaler Gateway is present in the environment.
- Identify affected versions and establish whether vulnerable services are exposed or reachable.
- Apply mitigations and kill all active and persistent sessions per vendor instructions [https://www.netscaler.com/blog/news/cve-2023-4966-critical-security-update-now-available-for-netscaler-adc-and-netscaler-gateway/] OR discontinue use of the product if mitigations are unavailable.
- Review relevant security telemetry for evidence of attempted or successful exploitation.
- Document the remediation decision and track it to verified completion.
Vendor remediation
Patch and remediation links
Use the vendor source below to confirm the correct fixed version, package or mitigation for your affected product.
Technical details
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CWE
- CWE-119
- Affected versions
- Citrix NetScaler ADC and NetScaler Gateway; Citrix Netscaler Application Delivery Controller (Start Including: 14.1, End Excluding: 14.1-8.50); Citrix Netscaler Gateway (Start Including: 14.1, End Excluding: 14.1-8.50)
- Published
- 10 October 2023
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
Signal timeline
- CVE published
- Added to CISA KEV
- Latest EPSS score: 100.0%
- Signal calculated at 86