CISA Known Exploited Vulnerability (KEV)
Citrix NetScaler ADC and Gateway Out-of-Bounds Read Vulnerability
July 10, 2025
July 11, 2025
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Description
Insufficient input validation leading to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
References
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420
- https://horizon3.ai/attack-research/attack-blogs/cve-2025-5777-citrixbleed-2-write-up-maybe/
- https://labs.watchtowr.com/how-much-more-must-we-bleed-citrix-netscaler-memory-disclosure-citrixbleed-2-cve-2025-5777/
- https://www.bleepingcomputer.com/news/security/cisa-tags-citrix-bleed-2-as-exploited-gives-agencies-a-day-to-patch/
- https://www.netscaler.com/blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-2025-5777/
- https://www.theregister.com/2025/07/10/cisa_citrixbleed_kev/
- https://doublepulsar.com/citrixbleed-2-exploitation-started-mid-june-how-to-spot-it-f3106392aa71
- https://reliaquest.com/blog/threat-spotlight-citrix-bleed-2-vulnerability-in-netscaler-adc-gateway-devices/