Home / Vulnerabilities / CVE-2023-4966
CRITICAL SEVERITY Ransomware Linked
CVE-2023-4966 Citrix · NetScaler ADC and NetScaler Gateway

Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability

Critical Threat Advisory: This vulnerability is documented in active Ransomware campaigns. Immediate remediation required.

Technical Severity

CVSS v3.1 Metrics

CRITICAL
9.4 / 10
Minimal Risk Critical
Vector Specification
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
Exploitation Likelihood

EPSS Prediction

94.35 %
Predictive Probability
Percentile Rank
100.0 th

Documented as more likely to be exploited than 100.0% of known CVEs.

Detection Date

Oct 18, 2023

Remediation Due

Nov 08, 2023

CISA Catalog Active

Threat Analysis

Citrix NetScaler ADC and NetScaler Gateway contain a buffer overflow vulnerability that allows for sensitive information disclosure when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server.

Remediation Directive

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.

External Intelligence

https://www.netscaler.com/blog/news/cve-2023-4966-critical-security-update-now-available-for-netscaler-adc-and-netscaler-gateway/,

https://www.netscaler.com/blog/news/cve-2023-4966-critical-security-update-now-available-for-netscaler-adc-and-netscaler-gateway/,
NVD

National Vulnerability Database

https://nvd.nist.gov/vuln/detail/CVE-2023-4966