Citrix has launched security updates to deal with a essential flaw affecting NetScaler ADC that it stated has been exploited within the wild.
The vulnerability, tracked as CVE-2025-6543, carries a CVSS rating of 9.2 out of a most of 10.0.
It has been described as a case of reminiscence overflow that might end in unintended management stream and denial-of-service. Nonetheless, profitable exploitation requires the equipment to be configured as a Gateway (VPN digital server, ICA Proxy, CVPN, RDP Proxy) or AAA digital server.
The shortcoming impacts the under variations –
- NetScaler ADC and NetScaler Gateway 14.1 previous to 14.1-47.46
- NetScaler ADC and NetScaler Gateway 13.1 previous to 13.1-59.19
- NetScaler ADC and NetScaler Gateway 12.1 and 13.0 (weak and end-of-life)
- NetScaler ADC 13.1-FIPS and NDcPP previous to 13.1-37.236-FIPS and NDcPP
“Safe Personal Entry on-prem or Safe Personal Entry Hybrid deployments utilizing NetScaler cases are additionally affected by the vulnerabilities,” Citrix stated.
“Clients have to improve these NetScaler cases to the advisable NetScaler builds to deal with the vulnerabilities.”
The corporate didn’t reveal how the flaw is being exploited in real-world assaults, however stated “exploits of CVE-2025-6543 on unmitigated home equipment have been noticed.”
The disclosure comes shortly after Citrix patched one other critical-rated security flaw in NetScaler ADC (CVE-2025-5777, CVSS rating: 9.3) that might be exploited by risk actors to achieve entry to inclined home equipment.
