CVE-2019-5544 Scanner

VMware Horizon DaaS is widely used in enterprise environments to deliver virtual desktops and applications through a cloud-based architecture. It is managed by IT administrators to provide virtual workspace solutions for end-users. Typically, it is deployed in both private and public clouds to enhance business flexibility and scalability. This desktop-as-a-service solution is favored for its ability to reduce the complexities of managing desktop environments. It supports various operating systems and is crucial for companies looking to streamline their IT infrastructure. Users benefit from a seamless virtual desktop experience.

The Denial of Service (DoS) vulnerability in VMware Horizon DaaS arises from a heap overflow condition in the OpenSLP service. When exploited, it can cause the server to crash or become unresponsive, effectively disrupting services. The vulnerability has a critical impact level as it can be exploited remotely without authentication. It's due to improper handling of certain inputs in network services, leading to memory corruption. Attackers can target this vulnerability to execute arbitrary code or crash systems, which may require a manual restart. Network stability and service availability can be heavily impacted, causing business disruption.

The vulnerability is located in the OpenSLP component of VMware Horizon DaaS, where an improper memory handling issue allows for heap overflow. When specific network packets are sent to the service, it can cause an overwrite of the heap memory structure. The condition is due to inadequate validation of received data sizes and bounds. Attackers exploit this by sending crafted packets via a particular port, leading to memory corruption. The vulnerability does not require authentication, increasing its accessibility for attackers. The flaw is critical and needs immediate attention to prevent downtimes.

If this vulnerability is exploited, attackers could cause the affected systems to crash, resulting in denial of service (DoS). This can lead to unexpected downtime and interrupt operations that rely on VMware Horizon DaaS. The business impact includes loss of productivity and potential financial ramifications due to service outages. Furthermore, successful exploitation might allow for more severe attacks, such as remote code execution, depending on the heap overflow's effect. Ensuring continuous availability of systems is jeopardized, making quick remediation essential to maintain business continuity.

REFERENCES

• https://nvd.nist.gov/vuln/detail/CVE-2019-5544
• https://github.com/dgh05t/VMware_ESXI_OpenSLP_PoCs
• http://www.openwall.com/lists/oss-security/2019/12/10/2
• http://www.openwall.com/lists/oss-security/2019/12/11/2
• https://access.redhat.com/errata/RHSA-2019:4240