CVE-2022-31002 is a medium-severity vulnerability classified as CWE-125 (Out-of-bounds Read) affecting the sofia-sip library, an open-source Session Initiation Protocol (SIP) User-Agent component used by FreeSWITCH. FreeSWITCH is a widely used telephony platform that supports voice, video, and text communications. The vulnerability exists in versions of sofia-sip prior to 1.13.8. An attacker can exploit this flaw by sending a specially crafted SIP message containing a malicious Session Description Protocol (SDP) payload, specifically a URL ending with a percent sign ('%'). This malformed input triggers an out-of-bounds read condition within the sofia-sip parser, which can cause the FreeSWITCH service to crash, resulting in a denial of service (DoS). The root cause is improper bounds checking when processing the URL in the SDP, leading to memory access beyond allocated buffers. While no known exploits are currently reported in the wild, the vulnerability is publicly disclosed and patched in version 1.13.8 of sofia-sip. The attack does not require authentication but does require the attacker to send crafted SIP messages to the target system. User interaction is not needed beyond the reception of the malicious SIP message. The impact is primarily on availability due to service crashes, with no direct indication of confidentiality or integrity compromise. However, disruption of telephony services can have significant operational consequences. The vulnerability affects any FreeSWITCH deployment using vulnerable sofia-sip versions, particularly those exposed to untrusted SIP traffic such as public-facing VoIP gateways or session border controllers.

For European organizations, the impact of CVE-2022-31002 can be significant in sectors relying heavily on VoIP communications, including telecommunications providers, call centers, emergency services, and enterprises with unified communications infrastructure. A successful exploitation could cause service outages, disrupting voice and video communications, potentially affecting business continuity and critical communications. This may lead to operational downtime, loss of productivity, and reputational damage. In regulated industries such as finance and healthcare, communication outages could also result in compliance issues. Although the vulnerability does not directly expose sensitive data or allow code execution, the denial-of-service effect can be leveraged as part of a larger attack campaign or to cause targeted disruption. Organizations with FreeSWITCH deployments exposed to the internet or untrusted networks are at higher risk. Given the widespread use of FreeSWITCH and sofia-sip in European telephony infrastructure, the vulnerability could affect a broad range of organizations, especially those that have not applied the patch or use customized versions of the software.

To mitigate this vulnerability, European organizations should immediately upgrade sofia-sip to version 1.13.8 or later, which contains the official patch addressing the out-of-bounds read. If upgrading is not immediately feasible, organizations should implement network-level protections such as SIP-aware firewalls or session border controllers (SBCs) to filter and validate incoming SIP messages, blocking malformed or suspicious SDP payloads, especially those containing URLs ending with '%'. Deploying anomaly detection systems that monitor SIP traffic for irregular patterns can help identify exploitation attempts. Additionally, organizations should restrict exposure of FreeSWITCH servers to trusted networks only, avoiding direct exposure to the public internet where possible. Regularly auditing and updating telephony infrastructure components and maintaining an inventory of software versions will help ensure timely patching. Logging and monitoring FreeSWITCH service stability can provide early warning of exploitation attempts. Finally, organizations should review incident response plans to include scenarios involving VoIP service disruption.