Citrix NetScaler ADC and Gateway Buffer Overflow Vulnerability
Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
What happened
Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
CISA lists it as exploited, added 30 Jun 2025.
Does it affect you
Names Citrix NetScaler ADC. Enter the product and version you run to place it against the affected range the vendor published.
What to do
- Follow the vendor advisory for the fixed release and any interim mitigation.
support.citrix.com - Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
cisa.gov
CISA’s notes for this entry:
Affected, as published to NVD
- citrix-adc
- Citrix NetScaler ADC: 13.1 up to the fix in 13.1-37.236
The record
- NVD status
- Analyzed
- Published
- 25 Jun 2025, last modified 17 Jun 2026 (NVD)
- Severity
- CVSS 3.1 base score 9.8, Critical — computed here from the vector; NVD states 9.8.
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weakness
- CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer (NVD; names by MITRE)
- Exploitation
- Listed in CISA’s Known Exploited Vulnerabilities catalogue since 30 Jun 2025; federal remediation due 21 Jul 2025. CISA entry
- Exploit probability
- EPSS 10.6%, 96th percentile — FIRST, scored 23 Oct 2026. FIRST EPSS
- Vendor
- Citrix · NetScaler ADC and Gateway (CISA)
References on the NVD record
- support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694788Vendor Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-6543US Government Resource
Sources
The verdict above is computed from the products and versions you entered and the affected ranges the vendor published to NVD. It does not inspect your environment, and this site never reports a product as unaffected: why.