CVE-2025-6543
Citrix NetScaler ADC and Gateway
Citrix NetScaler ADC and Gateway Buffer Overflow Vulnerability
What it is
Citrix NetScaler ADC and Gateway contain a buffer overflow vulnerability leading to unintended control flow and Denial of Service. NetScaler must be configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.
What to do
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vendor notices and references
- support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694788
- www.netscaler.com/blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-
- nvd.nist.gov/vuln/detail/CVE-2025-6543
Description and required action as published by CISA. Full record at NVD.
Other Citrix entries on the list
- NetScaler Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability CVE-2026-88779 · Oct 4, 2026
- NetScaler Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability CVE-2026-88772 · Sep 27, 2026
- NetScaler Citrix NetScaler Improper Input Validation Vulnerability CVE-2026-88771 · Sep 27, 2026
- NetScaler Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability CVE-2026-19490 · Sep 9, 2026
- NetScaler ADC and NetScaler Gateway Citrix NetScaler ADC and NetScaler Gateway Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability CVE-2026-8452 · Aug 26, 2026
- NetScaler Citrix NetScaler Out-of-Bounds Read Vulnerability CVE-2026-3055 · Mar 30, 2026