Critical severity · published Jun 25, 2025
CVE-2025-6543
Memory overflow vulnerability leading to unintended control flow and Denial of Service
In wildKEV
9.8
CVSS
10.4%
EPSS
Yes
On KEV
Description
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
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)10.4% · higher than 96% of CVEs
Exploited in the wildYes
CISA KEVListed Jun 30, 2025
Federal remediation dueJul 21, 2025
Ransomware campaign useNot known
Affected products
Which versions
NA
NetScaler ADC · Citrix
13.1 before 13.1-37.236; 13.1 before 13.1-37.236; 13.1 before 13.1-59.19; 14.1 before 14.1-47.46 · source: NVD
AD
ADC · NetScaler
14.1 before 47.46; 13.1 before 59.19; 13.1 FIPS and NDcPP before 37.236 · source: vendor
GA
Gateway · NetScaler
14.1 before 47.46; 13.1 before 59.19; 13.1 FIPS and NDcPP before 37.236 · source: vendor
NA
NetScaler ADC and Gateway · Citrix
All versions, or not specified · source: KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-6543
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-6543
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
support.citrix.com
https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694788
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