CISA Warns of Citrix NetScaler Vulnerability Actively Exploited in Attacks - CyberSecurityNews

HomeCyber Security News CISA Warns of Citrix NetScaler Vulnerability Actively Exploited in Attacks By Abinaya March 31, 2026 The Cybersecurity and Infrastructure Security Agency (CISA) has issued an urgent warning regarding a critical vulnerability affecting Citrix NetScaler products. Identified as CVE-2026-3055, this security flaw has been officially added to CISA’s Known Exploited Vulnerabilities (KEV) catalog following confirmed evidence of active exploitation in the wild. Network defenders and system administrators are urged to take immediate action to secure their environments against potential breaches. The vulnerability specifically impacts Citrix NetScaler ADC (formerly known as Citrix ADC), NetScaler Gateway (formerly Citrix Gateway), as well as the NetScaler ADC FIPS and NDcPP models. Citrix NetScaler Vulnerability Exploited The core issue lies in an out-of-bounds read vulnerability, which is technically categorized under CWE-125. This dangerous flaw presents itself when the affected appliances are configured to operate as a Security Assertion Markup Language (SAML) Identity Provider (IdP). By exploiting this weakness, a remote attacker could trigger a memory overread. In practical terms, this allows malicious actors to access sensitive information stored directly in the system’s memory. Because the appliance is acting as an authentication hub in this configuration, a memory exposure could easily compromise authentication tokens, user credentials, or other critical session data needed to access the wider corporate network. By adding CVE-2026-3055 to the KEV catalog, CISA confirms that threat actors are actively leveraging this vulnerability in real-world attacks. While the agency notes that it is currently unknown if the flaw is being utilized in ransomware campaigns, the active exploitation of any edge gateway appliance remains a severe threat. Threat actors frequently target internet-facing authentication devices like NetScaler to establish an initial foothold into enterprise networks. CISA has mandated a highly accelerated remediation timeline for this specific threat. Federal Civilian Executive Branch (FCEB) agencies have been given a strict deadline of April 2, 2026, to secure their vulnerable systems in accordance with Binding Operational Directive (BOD) 22-01. Although the directive targets federal agencies, CISA urges all private organizations to act immediately and apply vendor mitigations without delay. If proper patches or mitigations cannot be applied, or if they remain unavailable for specific legacy systems, organizations are strongly advised to discontinue the use of the product until it can be properly secured. Using the KEV catalog as a primary input for vulnerability management prioritization remains one of the most effective ways for organizations to keep pace with emerging threat activity. Follow us on Google News, LinkedIn, and X for daily cybersecurity updates. Contact us to feature your stories. Tags cyber security cyber security news Copy URL Linkedin Twitter ReddIt Telegram Abinayahttps://cybersecuritynews.com/ Abi is a Security Editor and fellow reporter with Cyber Security News. She is covering various cyber security incidents happening in the Cyber Space. Trending News Critical Microsoft 365 Copilot Vulnerabilities Expose sensitive Information Hackers Deploy Modular RAT With Credential Theft and Screenshot Capture Capabilities Massive 2.45B-Request DDoS Attack Used 1.2 Million IPs to Evade Rate Limits Microsoft Edge Stores All Saved Passwords in Cleartext Process Memory at Launch Popular Go Library fsnotify Raises Supply Chain Alarms After Maintainer Access Changes Latest News Cyber Security Google Warns of Hackers Using AI to Create Working Zero-Day Exploit Cyber Security News Hackers Use PlugX-Like DLL Sideloading Chain in Fake Claude Malware Campaign Cyber Security News Hackers Use Fake DeepSeek TUI GitHub Repositories to Deliver Malware Cyber Security News ShinyHunters Breaches Instructure Canvas LMS Through Free-For-Teacher Account Program Cyber Security News Crimenetwork Takedown Exposes 22,000 Users and Over 100 Illegal Sellers