Citrix has released a critical security bulletin addressing a vulnerability affecting NetScaler ADC (formerly Citrix ADC) and NetScaler Gateway (formerly Citrix Gateway). Citrix NetScaler is an all-in-one load balancer, web application firewall (WAF), virtual private network (VPN) gateway and SSL offloading tool for web applications.
- CVE-2025-6543 is a ‘memory overflow’ vulnerability with a CVSSv4 base score of 9.2. Successful exploitation could allow a remote unauthenticated attacker to gain unintended control flow and perform denial-of-service (DoS) in NetScaler ADC and NetScaler Gateway. NetScaler is only vulnerable to CVE-2025-6543 when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.
Read more…
Source: NHS Digital
Sign up for our Newsletter
The latest news and insights delivered right to your inbox.
Related:
- Google: Eleven zero-days detected in the wild in the first half of 2020
August 3, 2020
According to data collected by Google’s Project Zero security team, there have been 11 zero-day vulnerabilities exploited in the wild in the first half of the year. The current number puts 2020 on track to have just as many zero-days as 2019 when Google security researchers said they tracked 20 zero-days all of last year. Details about ...
- Billions of Devices Impacted by Secure Boot Bypass
July 29, 2020
Billions of Windows and Linux devices are vulnerable to cyberattacks stemming from a bug in the GRUB2 bootloader, researchers are warning. GRUB2 (which stands for the GRand Unified Bootloader version 2) is the default bootloader for the majority of computing systems. Its job is to manage part of the start-up process – it either presents a ...
- Critical Bugs in Utilities VPNs Could Cause Physical Damage
July 29, 2020
Remote code-execution vulnerabilities in virtual private network (VPN) products could impact the physical functioning of critical infrastructure in the oil and gas, water and electric utilities space, according to researchers. Researchers at Claroty found that VPNs used to provide remote access to operational technology (OT) networks in industrial systems are vulnerable to an array of security ...
- Mirai Botnet Exploit Weaponized to Attack IoT Devices via CVE-2020-5902
July 28, 2020
Following the initial disclosure of two F5 BIG-IP vulnerabilities on the first week of July, we continued monitoring and analyzing the vulnerabilities and other related activities to further understand their severities. Based on the workaround published for CVE-2020-5902, we found an internet of things (IoT) Mirai botnet downloader (detected by Trend Micro as Trojan.SH.MIRAI.BOI) that ...
- Attackers Exploiting High-Severity Network Security Flaw, Cisco Warns
July 27, 2020
Cisco is warning that a high-severity flaw in its network security software is being actively exploited – allowing remote, unauthenticated attackers to access sensitive data. Patches for the vulnerability (CVE-2020-3452) in question, which ranks 7.5 out of 10 on the CVSS scale, were released last Wednesday. However, attackers have since been targeting vulnerable versions of the software, ...
- Kubernetes Vulnerability Puts Clusters at Risk of Takeover (CVE-2020-8558)
July 27, 2020
A security issue assigned CVE-2020-8558 was recently discovered in the kube-proxy, a networking component running on Kubernetes nodes. The issue exposed internal services of Kubernetes nodes, often run without authentication. On certain Kubernetes deployments, this could have exposed the api-server, allowing an unauthenticated attacker to gain complete control over the cluster. An attacker with this ...

