CVE-2025-54957 is a critical security vulnerability affecting Dolby UDC versions 4.5 through 4.13, specifically within the DD+ audio decoder component. The flaw arises during the processing of malformed DD+ bitstreams containing Evolution data. The decoder's evo_priv.c module performs a length calculation for writing this data into a buffer, but this calculation can overflow due to an integer wraparound (CWE-190). This overflow causes the allocated buffer size to be insufficient, rendering subsequent out-of-bounds write checks ineffective and resulting in an out-of-bounds write (CWE-787). Such memory corruption can lead to a crash of the DD+ decoder process and potentially enable remote attackers to execute arbitrary code or cause denial of service. The vulnerability requires no privileges and no user interaction, making it remotely exploitable over a network vector. The CVSS v3.1 base score of 9.8 reflects its critical severity, with impacts on confidentiality, integrity, and availability. Although no exploits are currently known in the wild, the nature of the vulnerability and its ease of exploitation make it a high-risk threat. Dolby UDC is widely used in media playback, streaming devices, and content creation tools, which increases the attack surface. The lack of available patches at the time of disclosure necessitates immediate risk mitigation through network controls and input validation.

For European organizations, the impact of CVE-2025-54957 can be severe, particularly for those involved in media production, broadcasting, streaming services, and consumer electronics that utilize Dolby UDC for audio decoding. Exploitation could lead to remote code execution, allowing attackers to compromise systems, steal sensitive media content, disrupt services, or pivot within networks. The vulnerability threatens confidentiality by potentially exposing protected content, integrity by enabling tampering with audio streams or system files, and availability by causing crashes or denial of service. Given the critical CVSS score and no need for authentication, attackers could exploit this vulnerability at scale, targeting media servers, content delivery networks, and end-user devices. This could result in significant operational disruptions and reputational damage. The widespread use of Dolby technologies in European media industries and consumer markets amplifies the risk. Additionally, the potential for supply chain attacks exists if compromised media files are distributed through legitimate channels.

1. Monitor Dolby's official channels for patches addressing CVE-2025-54957 and apply them immediately upon release. 2. Until patches are available, implement strict input validation and filtering on all incoming DD+ bitstreams to detect and block malformed or suspicious audio data. 3. Employ sandboxing or containerization techniques to isolate the Dolby UDC decoder process, limiting the impact of potential exploitation. 4. Restrict network exposure of systems running Dolby UDC to trusted sources only, minimizing the attack surface. 5. Use intrusion detection/prevention systems (IDS/IPS) with updated signatures to identify exploitation attempts targeting this vulnerability. 6. Conduct security audits and code reviews of any custom integrations involving Dolby UDC to identify and remediate unsafe handling of audio streams. 7. Educate media production and IT teams about the risks and signs of exploitation to enhance incident response readiness. 8. Consider deploying application-layer firewalls or proxies that can analyze and sanitize multimedia streams before processing.