What is CVE-2025-5777?
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
Timeline
- 2025-06-17Published to the U.S. National Vulnerability Database (NVD)
- 2025-07-10Added to the CISA Known Exploited Vulnerabilities (KEV) catalog
- 2025-07-11CISA federal remediation deadline (BOD 22-01)
- 2026-07-03First covered in a defend.network daily briefing
- 2026-08-04NVD record last updated
CISA Known Exploited Vulnerability
Citrix NetScaler ADC and Gateway Out-of-Bounds Read Vulnerability
Affected product
Citrix NetScaler ADC And Gateway
NVD also lists CPE entries for: Citrix Netscaler Application Delivery Controller, Citrix Netscaler Gateway
Remediation Steps
- Apply the vendor security update for Citrix Bleed 2 (Citrix NetScaler) as a priority.
- Restrict network exposure of the affected service to trusted sources until patched.
- Review logs and detections for indicators of exploitation.
- Confirm fixed versions against the official vendor advisory before deploying.
References
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420
- https://citrixbleed.com
- https://horizon3.ai/attack-research/attack-blogs/cve-2025-5777-citrixbleed-2-write-up-maybe/
- https://nvd.nist.gov/vuln/detail/CVE-2025-5777
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Referenced in our briefings & reports
- Vulnerability Priority Report – Week 5 of June 2026 (June 29 – July 5)
- NetNut seized; Citrix Bleed 2 exploited; ToddyCat hijacks Gmail via OAuth (2026-07-03)
Browse all tracked CVEs in the defend.network CVE database →
🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.