CVE-2025-5777: Citrix NetScaler ADC and Gateway Out-of-Bounds Read Vulnerability
Citrix NetScaler ADC and Gateway contain an out-of-bounds read vulnerability due to insufficient input validation. This vulnerability can lead to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.
| Vendor | Citrix |
|---|---|
| Product | NetScaler ADC and Gateway |
| Date added to KEV | 2025-07-10 |
| Due date (BOD 22-01) | 2025-07-11 |
| Known ransomware campaign use | Known |
| CWE | CWE-125 |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
What to do
- Identify every instance of Citrix NetScaler ADC and Gateway in your environment (asset inventory, EDR, vulnerability scanner).
- Apply CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Federal civilian agencies must act by 2025-07-11 under BOD 22-01; other organizations can use the same date as a target.
- Because ransomware use is known, check for signs of compromise and confirm backups are offline and tested.
- Check the vendor advisory and NVD entry linked below for affected versions, then record the fix in your change log.
This CVE is flagged by CISA as known to be used in ransomware campaigns. Rehearse your response before you need it: Ransomware tabletop exercise kit (Runbook Foundry).