WATCHExploited vulnerability
Citrix NetScaler
Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
What's happening and what to do
An attacker can crash Citrix NetScaler devices through a memory buffer bug, and this flaw is being actively exploited in the wild. Citrix NetScaler ADC (formerly Citrix ADC) and Citrix NetScaler Gateway (formerly Citrix Gateway). Apply the vendor's update now and check for signs of compromise.
AI summary of the sources on this page. Regenerated when a source changes.
Signals over time
- 2026-10-04Added to CISA's Known Exploited Vulnerabilities catalog.
- 2026-10-07Federal patch deadline for US agencies.
- 2026-11-03 21:55First seen here.
Source text
Citrix NetScaler ADC (formerly Citrix ADC) and Citrix NetScaler Gateway (formerly Citrix Gateway) contain an improper restriction of operations within the bounds of a memory buffer vulnerability that could allow for a denial of service.