CVE-2025-1051 is a high-severity heap-based buffer overflow vulnerability affecting the Sonos Era 300 smart speaker, specifically version 81.1-58074. The flaw resides in the processing of ALAC (Apple Lossless Audio Codec) data streams. Due to improper validation of the length of user-supplied ALAC data before copying it into a heap buffer, an attacker can overflow the buffer. This overflow enables remote code execution (RCE) in the context of the 'anacapa' user on the device. Notably, exploitation does not require authentication or user interaction, and the attacker must be network-adjacent, meaning they need to be on the same local network or have network access to the device. The vulnerability is classified under CWE-122 (Heap-based Buffer Overflow) and was assigned CVSS v3.0 score 8.8, indicating high severity with impacts on confidentiality, integrity, and availability. The flaw was discovered and assigned by the Zero Day Initiative (ZDI) as ZDI-CAN-25865. No public exploits are known in the wild yet, and no patches have been linked at the time of publication. The vulnerability allows an attacker to execute arbitrary code, potentially taking full control of the affected Sonos Era 300 speaker, which could be leveraged for lateral movement, espionage, or disruption within a network environment.

For European organizations, this vulnerability poses a significant risk especially in environments where Sonos Era 300 devices are deployed in corporate offices, conference rooms, or smart building infrastructures. Exploitation could lead to unauthorized code execution on these devices, potentially allowing attackers to pivot into internal networks, intercept or manipulate audio streams, or disrupt device availability. Given the device's network connectivity and potential integration with other IoT or enterprise systems, the compromise could extend beyond the speaker itself. Confidentiality is at risk as attackers could eavesdrop or manipulate audio data; integrity and availability are also threatened due to possible device takeover or denial of service. The lack of authentication requirement lowers the barrier for attackers, increasing the threat level. While no exploits are currently known in the wild, the high CVSS score and ease of exploitation suggest that attackers may develop exploits rapidly, especially targeting environments with poor network segmentation or weak IoT security policies.

European organizations should immediately inventory their Sonos Era 300 devices and verify firmware versions. Since no patches are currently linked, organizations should implement network-level mitigations such as isolating Sonos devices on segmented VLANs with strict access controls to limit network adjacency to trusted users and systems only. Employ network monitoring to detect anomalous traffic patterns to/from these devices. Disable or restrict ALAC streaming if possible until a patch is available. Coordinate with Sonos for timely updates and apply patches as soon as they are released. Additionally, enforce strong network segmentation between IoT devices and critical enterprise infrastructure, and consider deploying intrusion detection/prevention systems (IDS/IPS) tuned to detect exploitation attempts targeting this vulnerability. Regularly update device firmware and maintain an asset management program to track IoT device security posture.