CVE-2025-2245 in GravityZone Update Server
Summary
by MITRE • 04/04/2025
A server-side request forgery (SSRF) vulnerability exists in the Bitdefender GravityZone Update Server when operating in Relay Mode. The HTTP proxy component on port 7074 uses a domain allowlist to restrict outbound requests, but fails to properly sanitize hostnames containing null-byte (%00) sequences. By crafting a request to a domain such as evil.com%00.bitdefender.com, an attacker can bypass the allowlist check, causing the proxy to forward requests to arbitrary external or internal systems.
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Analysis
by VulDB Data Team • 08/22/2025
This vulnerability represents a critical server-side request forgery flaw in Bitdefender GravityZone Update Server operating in Relay Mode, with significant implications for enterprise security infrastructure. The vulnerability stems from improper input validation within the HTTP proxy component that listens on port 7074, where the system maintains a domain allowlist to control outbound network requests. The flaw specifically manifests when the proxy processes hostnames containing null-byte sequences, which are typically used to terminate strings in many programming languages and operating systems. This weakness allows attackers to bypass the intended access controls by crafting malicious domain names that contain null-byte characters, effectively truncating the domain name and enabling access to unauthorized systems.
The technical exploitation of this vulnerability leverages the fundamental weakness in hostname sanitization where the proxy's validation logic fails to properly handle null-byte sequences in domain names. When an attacker submits a request with a domain such as evil.com%00.bitdefender.com, the system processes the null-byte as a string terminator, allowing the proxy to forward requests to the target system specified after the null-byte rather than the legitimate domain in the allowlist. This bypass mechanism operates at the application layer and can potentially enable access to internal network resources that should remain isolated from external threats. The vulnerability's impact is particularly severe because it can be exploited to access internal systems, databases, or other sensitive infrastructure that the proxy is meant to protect from external access.
The operational consequences of this vulnerability extend beyond simple network access bypass, as it can enable attackers to perform reconnaissance on internal network segments, potentially leading to further compromise of the security infrastructure. Security teams may face challenges in detecting this attack pattern because the malicious requests can appear to originate from legitimate internal systems, making network monitoring and incident response more complex. The vulnerability also presents opportunities for attackers to conduct data exfiltration or establish command and control channels through the compromised proxy server. Organizations using Bitdefender GravityZone in Relay Mode are particularly at risk, as the update server acts as a critical component in their security infrastructure, making it a prime target for attackers seeking to establish persistent access or disrupt security operations.
Mitigation strategies should focus on immediate patching of the affected software versions and implementation of additional network controls to monitor and restrict outbound connections from the proxy server. Organizations should consider implementing network segmentation to limit the potential impact of such attacks and deploy intrusion detection systems capable of identifying unusual patterns in outbound traffic. The vulnerability aligns with CWE-917, which addresses "Improper Neutralization of Special Elements used in an OS Command," and can be mapped to ATT&CK technique T1071.004 for application layer protocol tunneling. Regular security assessments of proxy configurations and input validation mechanisms should be conducted to prevent similar issues in other security infrastructure components. System administrators should also review and strengthen their domain allowlist implementations to ensure proper handling of special characters and null sequences in hostname validation processes.