Over 28,200 Citrix instances vulnerable to actively exploited RCE bug

A critical security vulnerability affecting over 28,200 Citrix instances worldwide has been actively exploited by threat actors, raising significant concerns in the cybersecurity community. The flaw, identified as CVE-2023-4965, is a remote code execution (RCE) bug that allows attackers to execute arbitrary code on vulnerable Citrix Application Delivery Controller (ADC) and Citrix Gateway devices. This vulnerability is particularly dangerous as it can be exploited without authentication, enabling attackers to gain full control over affected systems. Citrix, a leading company in application delivery and security solutions, has issued patches and urged users to update their systems immediately to mitigate the risk. The vulnerability has been actively exploited in the wild, with multiple attack campaigns targeting unpatched devices. Security researchers have observed increased scanning activity and exploitation attempts, highlighting the urgency for organizations to apply the necessary updates. The exploitation of CVE-2023-4965 can lead to severe consequences, including data breaches, ransomware deployment, and lateral movement within corporate networks. Attack groups are leveraging this vulnerability to gain initial access and establish persistent footholds. Organizations using Citrix ADC and Gateway products are advised to conduct thorough security assessments, monitor network traffic for suspicious activity, and implement additional security controls such as network segmentation and multi-factor authentication. This incident underscores the critical importance of timely patch management and proactive cybersecurity measures. As cyber threats continue to evolve, organizations must remain vigilant and prioritize the security of their infrastructure to prevent exploitation of known vulnerabilities. The cybersecurity community continues to monitor the situation closely and provide updates on mitigation strategies and threat actor tactics.

This Cyber News was published on www.bleepingcomputer.com. Publication date: Wed, 27 Aug 2025 16:55:17 +0000


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