Is CVE-2025-6543 actively exploited?

Yes. CVE-2025-6543 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, which means exploitation in the wild has been confirmed.

Can CVE-2025-6543 be exploited remotely?

The attack vector of CVE-2025-6543 has not been classified yet.

What is the CVSS score of CVE-2025-6543?

CVE-2025-6543 has not received a CVSS score yet.

HOME VULNERABILITIESCVE-2025-6543

HIGHCISA KEVIN THE WILD

CVE-2025-6543

Published: June 30, 2025

EPSS:2.71%probability of exploitation in 30 daysPercentile:85.7th

Official Description

Citrix NetScaler ADC and Gateway contain a buffer overflow vulnerability leading to unintended control flow and Denial of Service. NetScaler must be configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.

NVD Source

CISA KEV Advisory

Citrix NetScaler ADC and Gateway Buffer Overflow Vulnerability

Added to KEV: 2025-06-30Federal patch deadline: 2025-07-21

Required Action (CISA)

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Risk Analysis

This high-severity buffer overflow vulnerability in Citrix NetScaler ADC and Gateway can lead to a denial of service. While no CVSS score is provided, its inclusion in CISA's KEV catalog and an EPSS score of 0.02712 confirm active exploitation, making it an urgent concern.

This vulnerability is actively exploited in the wild and is present in CISA's KEV catalog. Exploitation requires NetScaler to be configured as a Gateway or AAA virtual server.

Recommended Action

Apply the latest security updates from Citrix for NetScaler ADC and Gateway. Ensure that NetScaler configurations are reviewed and hardened according to best practices.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2025-6543 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CISA has added CVE-2025-6543 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.