CVE-2026-20977 is a vulnerability classified under CWE-284 (Improper Access Control) found in Samsung Mobile Devices' Emergency Sharing feature prior to the SMR February 2026 Release 1. The vulnerability allows a local attacker to interrupt the Emergency Sharing functionality, which is designed to facilitate rapid communication during emergencies. The flaw arises because the access control mechanisms governing Emergency Sharing are insufficiently enforced, allowing unauthorized local actors to disrupt its operation. According to the CVSS 4.0 vector (AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N), the attack requires local access but no privileges, authentication, or user interaction, and it results in a high impact on availability. The vulnerability does not affect confidentiality or integrity directly but can severely impact availability by preventing emergency communications. No known exploits are currently reported in the wild, and no official patches have been linked yet, though the issue is addressed in the SMR February 2026 Release 1. The vulnerability was reserved in December 2025 and published in early February 2026, indicating a recent discovery and disclosure. The lack of required user interaction and privileges makes this vulnerability a concern for scenarios where an attacker can gain physical or local access to the device, such as in shared workspaces or public environments. The Emergency Sharing feature is critical for safety, and its disruption could delay emergency responses or assistance requests.

For European organizations, the impact of CVE-2026-20977 can be significant, particularly for sectors relying on Samsung Mobile Devices for emergency communications, such as healthcare, public safety, and critical infrastructure. Disruption of Emergency Sharing could delay or prevent timely emergency alerts, potentially endangering lives and causing operational disruptions. Organizations with mobile workforce or field operations using Samsung devices are at higher risk. The vulnerability's requirement for local access limits remote exploitation but raises concerns in environments where devices are shared, lost, or physically accessible to unauthorized personnel. The medium severity rating reflects the balance between the high availability impact and the local access requirement. In Europe, where emergency response systems are integrated with mobile technologies, this vulnerability could undermine trust in device reliability during critical incidents. Additionally, regulatory frameworks like GDPR emphasize the importance of maintaining availability and integrity of systems, so organizations may face compliance risks if emergency functionalities are compromised.

To mitigate CVE-2026-20977, European organizations should: 1) Prioritize timely deployment of the SMR February 2026 Release 1 update from Samsung as soon as it becomes available, as it addresses the improper access control issue. 2) Implement strict physical security controls to limit local access to Samsung Mobile Devices, especially in shared or public environments. 3) Enforce device usage policies that restrict unauthorized personnel from accessing or tampering with devices. 4) Monitor device logs and emergency feature usage for anomalies that could indicate attempts to disrupt Emergency Sharing. 5) Educate users about the importance of safeguarding their devices and reporting suspicious behavior promptly. 6) Consider additional endpoint protection solutions that can detect or prevent local tampering attempts. 7) For organizations with critical emergency communication needs, evaluate alternative or supplementary emergency alerting mechanisms to ensure redundancy. These steps go beyond generic advice by focusing on the specific access control weakness and the local attack vector.