CVE-2025-26783 is a high-severity vulnerability affecting the Radio Resource Control (RRC) component in various Samsung mobile and wearable processors, including the Exynos 2100, 1280, 2200, 1330, 1380, 1480, 2400, W1000, and modem chips 5300 and 5400. The vulnerability arises from incorrect handling of undefined values within the RRC module, which leads to a Denial of Service (DoS) condition. Specifically, when the RRC encounters unexpected or malformed input data, it fails to properly validate or sanitize these undefined values, causing the system to crash or become unresponsive. This vulnerability is classified under CWE-400, indicating a resource exhaustion or DoS issue. The CVSS v3.1 base score is 7.5, reflecting a high severity level, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), no impact on confidentiality or integrity (C:N/I:N), but high impact on availability (A:H). There are no known exploits in the wild at the time of publication, and no patches have been linked yet. The vulnerability affects a broad range of Samsung Exynos processors widely used in mobile phones and wearables, potentially impacting many devices globally. The root cause is improper input validation in the RRC protocol stack, which is critical for managing radio connections and mobility in cellular networks. Exploitation could be triggered remotely over the network without authentication or user interaction, making it a significant risk for service disruption.

For European organizations, the impact of CVE-2025-26783 could be substantial, especially for enterprises and service providers relying on Samsung Exynos-based devices for critical communications. The DoS condition could disrupt mobile connectivity, leading to loss of availability of voice, data, and IoT services. This can affect business operations, emergency communications, and customer service continuity. Enterprises with large fleets of Samsung mobile devices or wearables may experience widespread device outages or degraded network performance. Telecommunications providers using affected modems in infrastructure or customer premises equipment could face network instability or service interruptions. The lack of confidentiality or integrity impact limits data breach risks, but the availability impact alone can cause operational and reputational damage. The vulnerability’s network attack vector and no requirement for user interaction increase the likelihood of automated or remote exploitation attempts once public knowledge spreads. Although no exploits are currently known, the broad deployment of affected chips in consumer and enterprise devices across Europe elevates the threat potential. Organizations in sectors such as finance, healthcare, transportation, and public safety that depend on reliable mobile connectivity are particularly vulnerable to service disruptions caused by this flaw.

To mitigate CVE-2025-26783, European organizations should take a multi-layered approach: 1) Monitor Samsung and chipset vendors for official security patches or firmware updates addressing this vulnerability and apply them promptly once available. 2) Coordinate with mobile device management (MDM) solutions to identify and inventory devices using affected Exynos processors and prioritize patch deployment. 3) Implement network-level protections such as anomaly detection and intrusion prevention systems (IPS) to identify and block malformed RRC traffic patterns that could trigger the DoS condition. 4) Work with mobile network operators to monitor and filter suspicious signaling traffic targeting vulnerable devices. 5) For critical infrastructure and enterprise environments, consider deploying fallback communication methods or redundant connectivity options to maintain availability during potential DoS events. 6) Educate IT and security teams about the vulnerability’s characteristics to enhance incident response readiness. 7) Engage with Samsung support channels for guidance on interim mitigations or configuration changes that may reduce exposure. 8) Regularly review device and network logs for signs of attempted exploitation or unusual RRC activity. These steps go beyond generic advice by focusing on proactive device inventory, network traffic filtering specific to RRC protocol anomalies, and collaboration with operators and vendors to manage risk until patches are widely deployed.