A Critical Vulnerability in Open Virtual Network
CVE-2025-0650
CVE-2025-0650 is a significant security vulnerability identified in the Open Virtual Network (OVN). This flaw allows specially crafted UDP packets to bypass egress access control lists (ACLs) when configured on a logical switch that also has DNS records. The potential consequences of this vulnerability include unauthorized access to virtual machines and containers operating within the OVN network environment.Key Details
- Published Date: January 23, 2025
- Base Score: 8.1 (HIGH)
- Affected Systems: OVN installations with logical switches configured with DNS records and egress ACLs.
Technical Description
The vulnerability arises from the improper handling of UDP packets in OVN environments. When a logical switch is set up with both DNS records and egress ACLs, the system fails to enforce these ACLs correctly against specially crafted UDP packets. This oversight can lead to unauthorized access, compromising the security of virtual machines and containers that rely on OVN for network management.Sample Scenarios
- Unauthorized Access to Virtual Machines:
- A malicious actor crafts a UDP packet designed to exploit this vulnerability. By sending this packet into an OVN network where egress ACLs are expected to restrict access, the attacker could gain unauthorized entry into a virtual machine, potentially allowing them to manipulate or extract sensitive data.
- Container Security Breach:
- In a scenario where containers are deployed within an OVN-managed network, an attacker could leverage this flaw to bypass security measures. For instance, if a container running critical applications is configured with specific egress rules, the attacker could exploit the vulnerability to send malicious traffic that would otherwise be blocked, leading to potential data breaches or service disruptions.
Impact Assessment
The impact of CVE-2025-0650 is categorized as high due to its ability to bypass security controls that are fundamental for maintaining network integrity in virtualized environments. Organizations utilizing OVN must assess their configurations and consider implementing mitigations or updates as they become available.Recommendations
- Review Configuration:
- Administrators should review their OVN configurations, especially those involving logical switches with DNS records and egress ACLs.
- Monitor Network Traffic:
- Implement monitoring solutions to detect unusual UDP traffic patterns that may indicate exploitation attempts.
- Stay Updated:
- Keep abreast of updates from OVN maintainers regarding patches or workarounds for this vulnerability.
- Limit Exposure:
- Where possible, limit the exposure of sensitive virtual machines and containers by employing additional layers of security beyond standard ACLs.