CVE-2005-2719 in Ventrilo
Summary
by MITRE
Ventrilo 2.1.2 through 2.3.0 allows remote attackers to cause a denial of service (application crash) via a status packet that contains less data than specified in the packet header sent to UDP port 3784.
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Analysis
by VulDB Data Team • 01/26/2025
The vulnerability identified as CVE-2005-2719 affects Ventrilo versions 2.1.2 through 2.3.0 and represents a classic buffer underflow condition that can be exploited to trigger a denial of service scenario. This vulnerability specifically targets the UDP port 3784 which serves as the primary communication port for Ventrilo voice chat applications. The flaw occurs when the application receives a status packet that contains less data than what is declared in the packet header, creating a situation where the software attempts to process malformed data beyond the allocated buffer boundaries. This type of vulnerability falls under the CWE-129 category of Improper Validation of Array Index, which is a fundamental weakness in input validation that can lead to memory corruption and application instability.
The technical exploitation of this vulnerability demonstrates how network protocols can be manipulated to cause application crashes through malformed packet structures. When Ventrilo processes the status packet, it reads the header information to determine the expected packet size and then attempts to parse the data accordingly. However, when the actual data payload is smaller than the size indicated in the header, the application's parsing logic fails to properly validate the data boundaries, leading to memory access violations. This behavior aligns with the ATT&CK technique T1498.001 which describes Denial of Service through resource exhaustion and malformed input handling. The vulnerability specifically targets the UDP protocol implementation within Ventrilo's network stack, where the lack of proper bounds checking in the packet processing routine creates an exploitable condition that can be triggered remotely without authentication requirements.
The operational impact of this vulnerability extends beyond simple application instability, as it can be leveraged by remote attackers to disrupt legitimate service availability for users within the Ventrilo network. When exploited successfully, the vulnerability causes the Ventrilo application to crash and terminate unexpectedly, forcing users to reconnect to the voice chat service and potentially losing their communication session. This disruption can be particularly problematic in environments where Ventrilo is used for critical communication such as gaming communities, professional collaboration platforms, or emergency response coordination. The vulnerability's remote exploitability means that attackers can trigger the denial of service condition from outside the local network, making it a significant security concern for any organization relying on Ventrilo for voice communications. The affected versions span a considerable timeframe from 2.1.2 through 2.3.0, indicating that this was a persistent issue that required multiple patches to address properly. Organizations using these vulnerable versions faced the risk of sustained service disruption, particularly in high-traffic environments where multiple users might be simultaneously connected to the same Ventrilo server.
Mitigation strategies for this vulnerability should focus on immediate software updates and network-level protections. The most effective remediation involves upgrading to Ventrilo versions that have been patched to properly validate packet headers and implement robust bounds checking mechanisms for all incoming UDP data. Network administrators should also consider implementing firewall rules that limit access to UDP port 3784 to trusted sources only, thereby reducing the attack surface for remote exploitation attempts. Additionally, monitoring network traffic for malformed packets targeting this specific port can help detect potential exploitation attempts before they cause service disruption. The vulnerability highlights the importance of proper input validation in network applications and demonstrates how seemingly simple protocol parsing errors can result in significant availability issues. Organizations should also implement regular security assessments of their communication applications to identify similar buffer overflow vulnerabilities that could lead to more severe consequences including arbitrary code execution or privilege escalation. This vulnerability serves as a reminder of the critical importance of validating all network input data and implementing defensive programming practices to prevent memory corruption issues that can be exploited for denial of service attacks.