CVE-2022-26446 is a high-severity vulnerability affecting a broad range of MediaTek modem chipsets, including models MT2731 through MT8797, across multiple modem firmware versions such as LR12A, LR13, NR15, and NR16. The vulnerability resides in the 4G Radio Resource Control (RRC) component of the modem firmware, specifically related to improper input validation when processing concatenated System Information Block Type 12 (SIB12) messages, which are used for Commercial Mobile Alert System (CMAS) notifications. An attacker can exploit this flaw by sending specially crafted SIB12 messages that cause the modem system to crash, resulting in a denial of service (DoS) condition. Notably, exploitation requires no user interaction and no authentication or elevated privileges, making it remotely exploitable over the air interface. The vulnerability is classified under CWE-617 (Reachable Assertion), indicating that the system encounters an assertion failure due to unexpected input, leading to a crash. The CVSS v3.1 base score is 7.5, reflecting a high severity level with network attack vector, low attack complexity, no privileges required, no user interaction, and impact limited to availability (system crash). While no known exploits are currently reported in the wild, the wide deployment of affected MediaTek chipsets in mobile devices globally underscores the potential risk. The vendor has assigned a patch ID (MOLY00867883) and an internal issue ID (ALPS07274118), but no direct patch links are provided in the source information. This vulnerability can disrupt mobile device connectivity by crashing the modem, potentially impacting voice, data, and emergency alert services.

For European organizations, the impact of CVE-2022-26446 can be significant, especially for enterprises relying on mobile broadband connectivity for critical operations, including remote work, IoT deployments, and emergency communications. A successful DoS attack on the modem could lead to loss of cellular network connectivity, interrupting business communications and data transfer. This is particularly critical for sectors such as healthcare, transportation, utilities, and public safety, where continuous mobile connectivity is essential. Additionally, mobile network operators and managed service providers in Europe could face increased support costs and customer dissatisfaction due to service disruptions on devices using affected MediaTek chipsets. The vulnerability also poses risks to consumer devices, potentially affecting millions of users across Europe, which could indirectly impact organizations through supply chain and partner disruptions. Since exploitation requires no user interaction and can be triggered remotely, attackers could leverage this vulnerability in targeted campaigns or widespread denial of service attempts, potentially coinciding with geopolitical tensions or cyber conflict scenarios affecting Europe.

To mitigate CVE-2022-26446, European organizations and device manufacturers should prioritize applying firmware updates and patches provided by MediaTek or device vendors as soon as they become available. Network operators should monitor for unusual signaling or malformed SIB12 messages indicative of exploitation attempts and implement filtering or anomaly detection at the radio access network level to block suspicious CMAS message traffic. Device management platforms should enforce strict update policies to ensure modems run patched firmware versions (LR12A, LR13, NR15, NR16 or later). For critical infrastructure relying on mobile connectivity, consider deploying redundant communication paths or fallback mechanisms to minimize impact from modem outages. Security teams should also engage with mobile network providers to understand their mitigation strategies and incident response plans related to this vulnerability. Finally, raising awareness among end users about the importance of timely device updates can help reduce exposure.