CVE-2022-39244 is a classic buffer overflow vulnerability (CWE-120) found in the PJSIP pjproject multimedia communication library, specifically affecting versions prior to 2.13. PJSIP is an open-source C library widely used for multimedia communication, including VoIP applications. The vulnerability resides in multiple components of the library: the PJSIP parser, the PJMEDIA RTP decoder, and the PJMEDIA SDP parser. These components handle parsing of network protocol data related to multimedia sessions. The flaw arises because the code performs buffer copy operations without properly validating the size of the input data, leading to potential buffer overflow conditions. This can occur when processing data from untrusted clients, which may send specially crafted packets designed to overflow internal buffers. Exploitation could allow an attacker to execute arbitrary code, cause a denial of service (application crash), or potentially escalate privileges depending on the context in which the library is used. The vulnerability has been patched in the master branch as of commit c4d3498 and will be included in pjproject version 2.13 and later. No known workarounds exist, so upgrading is the primary mitigation. There are no known exploits in the wild at this time. The vulnerability requires that the vulnerable system accepts connections from untrusted clients, which is common in VoIP and multimedia communication environments. Because the flaw affects core parsing components, the impact could be significant if exploited, but exploitation requires network access and sending crafted multimedia protocol data. The vulnerability does not require authentication but does require interaction from an attacker-controlled client sending malicious packets. Overall, this is a medium severity vulnerability due to its potential impact balanced against the need for network access and crafted input.

For European organizations, the impact of CVE-2022-39244 could be considerable in sectors relying heavily on VoIP and multimedia communication systems that incorporate the pjproject library, such as telecommunications providers, call centers, unified communications platforms, and enterprises with integrated voice/video services. Successful exploitation could lead to remote code execution or denial of service, disrupting critical communication infrastructure. This could affect confidentiality if attackers gain code execution and access sensitive communications, integrity if data streams are manipulated, and availability if services crash or become unresponsive. Given the widespread use of PJSIP in open-source and commercial VoIP products, organizations that have not upgraded to pjproject 2.13 or later remain vulnerable. The lack of known exploits currently reduces immediate risk, but the presence of a buffer overflow in parsing code is a high-value target for attackers seeking remote compromise. European organizations with public-facing multimedia communication endpoints are particularly at risk, especially if these endpoints accept connections from untrusted networks or the internet. Disruption of communication services could have cascading effects on business operations, emergency services, and customer interactions. Additionally, regulatory requirements such as GDPR emphasize the protection of communication data, so exploitation leading to data breaches could have legal and reputational consequences.

The primary mitigation is to upgrade all instances of pjproject to version 2.13 or later, which includes the patch for this vulnerability. Organizations should conduct an inventory of all systems and applications using pjproject, including embedded devices and third-party VoIP products, to ensure they are updated. Since no workarounds exist, network-level protections can help reduce exposure: implement strict firewall rules to limit access to multimedia communication ports only to trusted networks or clients. Deploy intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection for malformed RTP/SDP packets to detect potential exploitation attempts. Employ network segmentation to isolate vulnerable multimedia communication servers from critical infrastructure. Monitor logs and network traffic for unusual patterns indicative of exploitation attempts. Vendors and integrators should verify that their products incorporate the patched pjproject version. For environments where immediate upgrade is not feasible, consider restricting access to multimedia services to internal networks only and enforce strong authentication and encryption to reduce attack surface. Regularly review and apply security advisories from pjproject and related vendors. Finally, conduct penetration testing and vulnerability assessments focusing on multimedia communication components to validate the effectiveness of mitigations.