Overview
CVE-2025-4321 describes a denial-of-service (DoS) vulnerability affecting Bluetooth devices utilizing the RS9116-WiseConnect SDK. This vulnerability can be triggered when the device receives malformed L2CAP (Logical Link Control and Adaptation Protocol) packets. Upon receiving such packets, the device enters a state requiring a hard reset to restore normal operation, effectively causing a denial of service.
Technical Details
The vulnerability stems from insufficient input validation within the RS9116-WiseConnect SDK’s L2CAP packet processing routines. When a malformed L2CAP packet is received, the SDK fails to handle the error gracefully, leading to a system crash or lock-up. The exact nature of the malformation that triggers the vulnerability is not publicly detailed in most advisories, requiring further investigation and reverse engineering to fully understand the root cause. The only known recovery method is a hard reset of the affected device.
CVSS Analysis
As of the published date (2025-11-17), both the severity and CVSS score for CVE-2025-4321 are listed as “N/A.” This typically indicates that the vendor (Silicon Labs in this case, through the RS9116-WiseConnect SDK) has not yet fully assessed the vulnerability or made a CVSS score publicly available. However, based on the description, the impact is a denial of service, which often translates to a medium to high severity depending on the context of the affected device and the ease of exploitation.
Possible Impact
The exploitation of CVE-2025-4321 can have significant consequences, particularly for devices integrated into critical systems. Potential impacts include:
- Device Unavailability: The primary impact is the interruption of service provided by the affected Bluetooth device.
- Operational Disruption: If the affected device controls or monitors a critical function (e.g., industrial control systems, medical devices), its unavailability can lead to broader operational disruptions.
- Security System Bypass: In scenarios where Bluetooth devices are used for security authentication or access control, a successful DoS attack could potentially bypass security measures.
Mitigation or Patch Steps
The recommended mitigation strategy is to apply the official patch or update provided by Silicon Labs for the RS9116-WiseConnect SDK. Specific steps may include:
- Check for Updates: Regularly monitor the Silicon Labs website and update channels for the latest SDK versions.
- Apply the Patch: Follow the vendor’s instructions for applying the security patch addressing CVE-2025-4321.
- Network Segmentation: Implement network segmentation to limit the potential impact of a successful attack. Isolate vulnerable devices from critical network segments.
- Monitor Bluetooth Traffic: Implement intrusion detection systems (IDS) or security information and event management (SIEM) solutions to monitor Bluetooth traffic for anomalous patterns that may indicate exploitation attempts.
