The Hacker News Logo
Subscribe to Newsletter

The Hacker News - Cybersecurity News and Analysis: Citrix ADC

Attackers Abusing Citrix NetScaler Devices to Launch Amplified DDoS Attacks

Attackers Abusing Citrix NetScaler Devices to Launch Amplified DDoS Attacks

December 24, 2020Ravie Lakshmanan
Citrix has issued an emergency advisory warning its customers of a security issue affecting its NetScaler application delivery controller (ADC) devices that attackers are abusing to launch amplified distributed denial-of-service (DDoS) attacks against several targets . "An attacker or bots can overwhelm the Citrix ADC [Datagram Transport Layer Security] network throughput, potentially leading to outbound bandwidth exhaustion," the company  noted . "The effect of this attack appears to be more prominent on connections with limited bandwidth." ADCs are purpose-built  networking appliances  whose function is to improve the performance, security, and availability of applications delivered over the web to end-users. The desktop virtualization and networking service provider said it's monitoring the incident and is continuing to investigate its impact on Citrix ADC, adding "the attack is limited to a small number of customers around the world." The iss
Citrix Issues Critical Patches for 11 New Flaws Affecting Multiple Products

Citrix Issues Critical Patches for 11 New Flaws Affecting Multiple Products

July 08, 2020Ravie Lakshmanan
Citrix yesterday issued new security patches for as many as 11 security flaws that affect its Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WAN Optimization edition (WANOP) networking products. Successful exploitation of these critical flaws could let unauthenticated attackers perform code injection, information disclosure, and even denial-of-service attacks against the gateway or the authentication virtual servers . Citrix confirmed that the aforementioned issues do not impact other virtual servers, such as load balancing and content switching virtual servers. Among the affected Citrix SD-WAN WANOP appliances include models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. The networking vendor also reiterated that these vulnerabilities were not connected to a previously fixed zero-day NetScaler flaw (tagged as CVE-2019-19781 ) that allowed bad actors to perform arbitrary code execution even without proper authentication. It also said there's no evidence
Citrix Releases Patches for Critical ADC Vulnerability Under Active Attack

Citrix Releases Patches for Critical ADC Vulnerability Under Active Attack

January 20, 2020Mohit Kumar
Citrix has finally started rolling out security patches for a critical vulnerability in ADC and Gateway software that attackers started exploiting in the wild earlier this month after the company announced the existence of the issue without releasing any permanent fix. I wish I could say, "better late than never," but since hackers don't waste time or miss any opportunity to exploit vulnerable systems, even a short window of time resulted in the compromise of hundreds of Internet exposed Citrix ADC and Gateway systems. As explained earlier on The Hacker News, the vulnerability, tracked as CVE-2019-19781 , is a path traversal issue that could allow unauthenticated remote attackers to execute arbitrary code on several versions of Citrix ADC and Gateway products, as well as on the two older versions of Citrix SD-WAN WANOP. Rated critical with CVSS v3.1 base score 9.8, the issue was discovered by Mikhail Klyuchnikov, a security researcher at Positive Technologies, w
Online Courses and Software

Sign up for cybersecurity newsletter and get latest news updates delivered straight to your inbox daily.