CVE-2025-5777: 
Citrix ADC VPX vulnerability analysis and mitigation

A critical security vulnerability identified as CVE-2025-5777 affects NetScaler ADC (formerly Citrix ADC) and NetScaler Gateway (formerly Citrix Gateway) products. The vulnerability, discovered in June 2025, is characterized by insufficient input validation leading to memory overread on the NetScaler Management Interface. With a CVSS v4.0 base score of 9.3 (CRITICAL), this vulnerability affects multiple versions including NetScaler ADC and NetScaler Gateway 14.1 before 14.1-43.56, version 13.1 before 13.1-58.32, and various FIPS-compliant versions (NVD, GBHackers).

The vulnerability stems from insufficient input validation that leads to memory overread issues. It specifically affects systems configured as Gateway services, including VPN virtual servers, ICA Proxy, Citrix Virtual Private Network (CVPN), Remote Desktop Protocol (RDP) Proxy, and Authentication, Authorization, and Accounting (AAA) virtual servers. The vulnerability has been assigned CWE-125 (Out-of-bounds Read) classification (NVD, Cybersecurity News).

Successful exploitation of this vulnerability could allow attackers to read sensitive memory contents, including credentials and configuration data. The high severity rating (CVSS score 9.3) indicates the potential for significant data exposure and system compromise. Systems configured as Gateway services are particularly at risk, with potential exposure of sensitive corporate data and network resources (GBHackers).

Cloud Software Group has released patched versions to address this vulnerability. Organizations are advised to upgrade to NetScaler ADC and Gateway version 14.1-43.56 or later, version 13.1-58.32 or later, or the corresponding FIPS-compliant releases. After upgrading, administrators should execute commands to terminate all active ICA and PCoIP sessions using 'kill icaconnection -all' and 'kill pcoipConnection -all'. Customers using Citrix-managed cloud services receive automatic updates (GBHackers).

The vulnerability was responsibly disclosed by security researchers from Positive Technologies and ITA MOD CERT (CERTDIFESA), who collaborated with Cloud Software Group to ensure a coordinated response before public disclosure. The critical nature of the vulnerability has prompted urgent security advisories from Cloud Software Group, emphasizing the immediate need for system updates (Cybersecurity News).