CVE-2022-24938 is a medium-severity vulnerability affecting the Ember ZNet stack developed by silabs.com, specifically version 1.0.0. The vulnerability arises from improper restriction of operations within the bounds of a memory buffer (CWE-119), leading to a stack overflow when the stack processes a malformed packet. This overflow triggers an assert condition that causes the affected device to reset immediately, clearing the error state. The vulnerability does not result in direct compromise of confidentiality or integrity but impacts availability by causing device resets. The CVSS 3.1 base score is 6.5, reflecting an attack vector that requires adjacent network access (AV:A), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), and no impact on confidentiality or integrity but high impact on availability (A:H). The vulnerability is exploitable remotely within the local network segment, without authentication or user interaction. No known exploits are currently reported in the wild, and no patches have been published yet. The vulnerability affects embedded devices using Ember ZNet 1.0.0, which is a Zigbee protocol stack commonly used in IoT and smart home devices for wireless communication. The stack's reset behavior upon overflow may cause temporary denial of service conditions, potentially disrupting network operations or device functionality in environments relying on Ember ZNet for critical communications.

For European organizations, the primary impact of CVE-2022-24938 is on the availability of IoT and embedded devices utilizing the Ember ZNet stack. This includes smart building automation, industrial control systems, smart metering, and other wireless sensor networks that rely on Zigbee communications. Repeated exploitation could lead to persistent device resets, causing service interruptions, degraded operational efficiency, or loss of monitoring and control capabilities. While the vulnerability does not expose sensitive data or allow code execution, the denial of service could affect critical infrastructure sectors such as energy, manufacturing, and smart city deployments. Organizations with large-scale IoT deployments or those integrating Ember ZNet-based devices into their operational technology (OT) environments may experience increased maintenance costs and operational risks. The lack of known exploits reduces immediate risk, but the ease of triggering the vulnerability without authentication or user interaction means attackers with local network access could disrupt device availability. This is particularly relevant in environments where network segmentation is weak or where wireless access is exposed.

To mitigate CVE-2022-24938, European organizations should first identify all devices running Ember ZNet 1.0.0 within their networks, focusing on IoT and embedded systems using Zigbee communications. Since no official patches are currently available, organizations should implement network-level controls to restrict access to the affected devices. This includes segmenting IoT networks from critical enterprise and OT networks, enforcing strict access control lists (ACLs) to limit which devices and users can send packets to Ember ZNet devices, and monitoring for anomalous packet patterns indicative of malformed packets. Deploying intrusion detection systems (IDS) with signatures or heuristics for malformed Zigbee packets can provide early warning of exploitation attempts. Additionally, organizations should work with silabs.com or device vendors to obtain firmware updates or patches as they become available. Where possible, consider upgrading to newer versions of Ember ZNet that address this vulnerability. For critical deployments, implementing redundancy and failover mechanisms can reduce the impact of device resets. Finally, conducting regular security assessments and penetration tests on IoT networks will help identify exposure and validate mitigation effectiveness.