CVE-2025-5777
HIGH severity · CVSS 7.5 · Out-of-bounds read · actively exploited (CISA KEV)
7.5CVSS HIGH exploited ransomware
Actively exploited in the wild (CISA Known Exploited Vulnerabilities).
Known use in ransomware campaigns. Added to KEV 2025-07-10. US federal agencies must patch by 2025-07-11.
Summary
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
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactHigh
Integrity impactNone
Availability impactNone
Exploit probability (EPSS)100%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products we track (1)
Recommendation
This vulnerability is being actively exploited in the wild — patch affected products urgently. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420Advisory
- https://citrixbleed.comAdvisory
- https://horizon3.ai/attack-research/attack-blogs/cve-2025-5777-citrixbleed-2-write-up-maybe/Advisory
- https://labs.watchtowr.com/how-much-more-must-we-bleed-citrix-netscaler-memory-disclosure-citrixbleed-2-cve-2025-5777/Advisory
- https://www.bleepingcomputer.com/news/security/cisa-tags-citrix-bleed-2-as-exploited-gives-agencies-a-day-to-patch/Advisory
- https://www.netscaler.com/blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-2025-5777/Advisory
- https://www.theregister.com/2025/07/10/cisa_citrixbleed_kev/
- https://doublepulsar.com/citrixbleed-2-exploitation-started-mid-june-how-to-spot-it-f3106392aa71Advisory