CVE-2025-65406 is a heap overflow vulnerability identified in the Live555 Streaming Media library version 2018.09.02, specifically within the MatroskaFile::createRTPSinkForTrackNumber() function. This function is responsible for creating RTP sinks for specific track numbers when processing Matroska (MKV) media files. The vulnerability arises from improper handling of crafted MKV files, which can cause a heap overflow condition. When exploited, this overflow can lead to a Denial of Service (DoS) by crashing the application or causing it to hang, thereby impacting the availability of the streaming service or device using the library. The vulnerability does not require any privileges (AV:N) but does require user interaction (UI:R), meaning the victim must open or process the malicious MKV file. The CVSS vector indicates no impact on confidentiality or integrity, only availability (A:H). No known exploits have been reported in the wild, and no patches have been released yet, which suggests that organizations should proactively monitor and prepare for remediation. The vulnerability is classified under CWE-122 (Heap-based Buffer Overflow), a common and critical class of memory corruption bugs that can lead to crashes or potentially more severe exploitation if combined with other vulnerabilities. Live555 is widely used in streaming media applications, embedded devices, and IoT products that handle RTP streaming and MKV files, making this vulnerability relevant to a broad range of systems.

For European organizations, the primary impact of CVE-2025-65406 is service disruption due to Denial of Service attacks. Organizations relying on Live555 for streaming media delivery, video conferencing, or embedded multimedia processing could experience outages or degraded service availability. This can affect telecommunications providers, media companies, broadcasters, and any enterprise using embedded devices that process MKV files. The lack of confidentiality or integrity impact limits data breach risks, but operational continuity could be compromised, leading to potential financial losses and reputational damage. Critical infrastructure sectors that depend on real-time media streaming, such as emergency services or transportation systems, may face operational risks if devices or services become unavailable. The requirement for user interaction means social engineering or phishing campaigns could be used to deliver malicious MKV files, increasing the attack surface. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits once the vulnerability becomes public knowledge.

1. Implement strict validation and sanitization of all MKV files before processing, using whitelisting or sandboxing techniques to isolate the media parsing components. 2. Restrict user ability to open or process untrusted MKV files, especially in environments where Live555 is used. 3. Monitor streaming media services and embedded devices for abnormal crashes or hangs that could indicate exploitation attempts. 4. Prepare to apply patches or updates from Live555 maintainers as soon as they become available; track vendor advisories closely. 5. Employ network-level protections such as intrusion detection systems (IDS) tuned to detect malformed MKV file traffic or unusual RTP stream behavior. 6. Educate users and administrators about the risks of opening untrusted media files and implement policies to limit exposure. 7. For embedded devices, consider firmware updates or configuration changes that limit exposure to crafted MKV files. 8. Conduct regular security assessments and penetration testing focused on media handling components to identify similar vulnerabilities proactively.