CVE-2025-6543NVD

Vulnerability Summary

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

Severity Level

CRITICAL(9.2)

Published Date

Jun 25, 2025

Last Modified

Jul 1, 2025

Exploitation Status

ACTIVE

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-119: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v4.0 Base Metrics — Score 9.2 (CRITICAL)

Attack VectorNetwork

Attack ComplexityHigh

Attack RequirementsPresent

Privileges RequiredNone

User InteractionNone

Confidentiality (Vulnerable System)High

Integrity (Vulnerable System)High

Availability (Vulnerable System)High

Confidentiality (Subsequent System)Low

Integrity (Subsequent System)Low

Availability (Subsequent System)Low

CVSS v3.1 Base Metrics — Score 9.8 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

Affected & Patched Versions

Affected Versions

Citrix Netscaler Application Delivery Controller >= 13.1 and < 13.1-37.236
Citrix Netscaler Application Delivery Controller >= 13.1 and < 13.1-59.19
Citrix Netscaler Application Delivery Controller >= 14.1 and < 14.1-47.46
Citrix Netscaler Gateway >= 13.1 and < 13.1-59.19
Citrix Netscaler Gateway >= 14.1 and < 14.1-47.46

Patched Versions

Citrix Netscaler Application Delivery Controller 13.1-37.236
Citrix Netscaler Application Delivery Controller 13.1-59.19
Citrix Netscaler Application Delivery Controller 14.1-47.46
Citrix Netscaler Gateway 13.1-59.19
Citrix Netscaler Gateway 14.1-47.46

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