Citrix has launched safety updates to deal with a crucial flaw affecting NetScaler ADC that it mentioned 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 would end in unintended management circulate and denial-of-service. Nevertheless, 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 beneath 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 Non-public Entry on-prem or Safe Non-public Entry Hybrid deployments utilizing NetScaler cases are additionally affected by the vulnerabilities,” Citrix mentioned.
“Clients must improve these NetScaler cases to the beneficial NetScaler builds to deal with the vulnerabilities.”
The corporate didn’t reveal how the flaw is being exploited in real-world assaults, however mentioned “exploits of CVE-2025-6543 on unmitigated home equipment have been noticed.”
The disclosure comes shortly after Citrix patched one other critical-rated safety flaw in NetScaler ADC (CVE-2025-5777, CVSS rating: 9.3) that might be exploited by risk actors to realize entry to inclined home equipment.
