CVE-2025-1049 Overview
CVE-2025-1049 is a heap-based buffer overflow [CWE-122] in the Sonos Era 300 smart speaker. The flaw resides in the speaker's processing of ID3 metadata tags and allows network-adjacent attackers to execute arbitrary code without authentication. Successful exploitation grants code execution in the context of the anacapa user account on the device. The vulnerability was reported through Trend Micro's Zero Day Initiative as ZDI-CAN-25601.
Critical Impact
Unauthenticated attackers on the same network segment can execute arbitrary code on Sonos Era 300 speakers by delivering crafted ID3 data, compromising device integrity and confidentiality.
Affected Products
- Sonos Era 300 speaker hardware
- Sonos S1 controller software
- Sonos S2 controller software
Discovery Timeline
- 2025-04-23 - CVE-2025-1049 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-1049
Vulnerability Analysis
The vulnerability lives in the firmware component that parses ID3 tags from audio files streamed or queued to the speaker. ID3 is the metadata container format used to embed title, artist, album, and other descriptive fields inside MP3 and related audio files. The parser copies attacker-controlled tag content into a fixed-size heap buffer without verifying that the source length fits the destination allocation.
An attacker on the adjacent network supplies an audio source containing oversized ID3 fields. When the Era 300 reads the metadata, the unchecked copy overruns the heap buffer and corrupts adjacent allocations. Attackers can shape the overflow to overwrite heap metadata or function pointers and redirect execution to attacker-supplied payloads. Code runs as the anacapa user, giving access to internal speaker services and the local network.
Root Cause
The root cause is missing length validation prior to a heap copy operation, classified as CWE-122 (Heap-based Buffer Overflow). The ID3 parsing routine trusts length values supplied in the metadata stream rather than constraining them against the destination buffer size.
Attack Vector
The attack requires adjacent network access, meaning the attacker must reach the speaker on the same Wi-Fi or wired LAN segment. No user interaction or credentials are required. Delivery vectors include malicious media files served from a local UPnP or DLNA source, hostile streaming endpoints reachable on the LAN, or queued playback content that exposes the speaker to manipulated ID3 metadata. Refer to the Zero Day Initiative Advisory ZDI-25-224 for additional technical context.
Detection Methods for CVE-2025-1049
Indicators of Compromise
- Audio files with malformed or oversized ID3v2 tag frames present on local media shares.
- Unexpected outbound connections from a Sonos Era 300 to non-Sonos infrastructure following media playback.
- Crashes, reboots, or anacapa process anomalies reported in Sonos diagnostic logs.
Detection Strategies
- Inspect SMB, UPnP, and DLNA traffic on the LAN for audio files containing ID3 frames that exceed normal size boundaries.
- Baseline network behavior of Sonos devices and alert on deviations such as new listening ports or unknown peer connections.
- Correlate speaker firmware diagnostic submissions with crash signatures associated with ID3 parsing.
Monitoring Recommendations
- Place IoT and audio devices on a segmented VLAN and log all egress with NetFlow or equivalent telemetry.
- Monitor wireless infrastructure for new or unauthorized stations joining the same SSID as Sonos devices.
- Track firmware version inventory for Sonos endpoints and alert when devices fall behind the current released build.
How to Mitigate CVE-2025-1049
Immediate Actions Required
- Apply the latest Sonos firmware and S1 or S2 controller updates to all Era 300 speakers.
- Restrict network access to Sonos devices so only trusted clients can deliver media streams.
- Audit media libraries and shared folders for untrusted audio files that the speaker may auto-index.
Patch Information
Sonos addressed the issue in firmware updates distributed through the S1 and S2 controller applications. Consult the Zero Day Initiative Advisory ZDI-25-224 for the vendor-coordinated fix reference. Enable automatic updates in the Sonos controller to receive future security fixes without manual intervention.
Workarounds
- Isolate Sonos Era 300 speakers on a dedicated IoT VLAN with no lateral access to user or server subnets.
- Disable network shares and streaming sources that expose the speaker to untrusted ID3 metadata.
- Block guest devices from reaching Sonos control and media ports using wireless client isolation.
# Example: restrict Sonos VLAN to controller subnet only
iptables -A FORWARD -s 10.20.30.0/24 -d 10.10.10.0/24 -p tcp --dport 1400 -j ACCEPT
iptables -A FORWARD -d 10.10.10.0/24 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
