Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability (CVE-2023-4966)
Severity: high · Patch status: unknown · Since 2023-10-18 · CVE-2023-4966
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. CISA added CVE-2023-4966 to its Known Exploited Vulnerabilities catalog on Oct 18, 2023, which means attackers are exploiting it in the wild. CISA reports known use in ransomware campaigns.
What to do
- 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.
- US federal agencies must remediate by Nov 8, 2023 (BOD 22-01); treat that as the outer limit.
Sources
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