Exploited· due 2023-11-08used in ransomware

CVE-2023-4966

Citrix NetScaler ADC and NetScaler Gateway

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.

Exploitation status

  • CISA has confirmed this is being exploited in the wild. That is an observation of real attacks, not a prediction.
  • It is known to have been used in ransomware campaigns.
  • US federal civilian agencies are required to remediate it by 2023-11-08. That deadline does not bind private companies, but it is a reasonable benchmark for how urgently CISA views it.

Required action

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.

CISA’s wording, unedited.

Scoring

CVSS
Not yet scored

Dates

Published
2023-10-18
Added to KEV
2023-10-18
Remediation due
2023-11-08
Sources
CISA KEV