CVE-2025-21043 is an out-of-bounds write vulnerability classified under CWE-787 found in the libimagecodec.quram.so library component used by Samsung Mobile Devices. This vulnerability exists in versions prior to the SMR (Security Maintenance Release) September 2025 Release 1. The flaw allows remote attackers to execute arbitrary code by exploiting improper memory handling in the image codec library, which processes image data. The vulnerability can be triggered remotely over the network without requiring any privileges (AV:N/PR:N), but it requires user interaction (UI:R), such as opening a specially crafted image or media file. Successful exploitation can lead to complete compromise of the device, impacting confidentiality, integrity, and availability (C:H/I:H/A:H). The CVSS v3.1 base score is 8.8, reflecting the ease of exploitation and the critical impact. No known exploits have been reported in the wild yet, but the vulnerability poses a significant risk due to the widespread use of Samsung mobile devices globally. The absence of detailed affected versions suggests that all devices running firmware prior to the specified SMR update are vulnerable. The vulnerability is particularly dangerous because it allows arbitrary code execution remotely, which could be leveraged to install malware, steal sensitive data, or disrupt device operations.

For European organizations, this vulnerability presents a serious threat to mobile device security, particularly for employees using Samsung mobile devices for business communications, data access, and remote work. Exploitation could lead to unauthorized access to corporate data, interception of communications, and potential lateral movement within enterprise networks if mobile devices are used as entry points. The high impact on confidentiality, integrity, and availability means that sensitive personal data, intellectual property, and critical business information could be compromised. Additionally, disruption of mobile device functionality could affect operational continuity. Given the reliance on mobile devices in sectors such as finance, government, healthcare, and critical infrastructure across Europe, the vulnerability could be exploited for espionage, data theft, or sabotage. The requirement for user interaction means phishing or social engineering campaigns could be used to trigger the exploit, increasing the risk to organizations with less mature security awareness programs.

1. Immediately monitor Samsung’s official security advisories and apply the SMR September 2025 Release 1 update or later as soon as it becomes available to ensure the vulnerability is patched. 2. Implement mobile device management (MDM) solutions to enforce timely patch deployment and restrict installation of untrusted applications or media files. 3. Educate users about the risks of opening unsolicited or suspicious image files or links, emphasizing caution with messages from unknown sources. 4. Employ network-level protections such as filtering and sandboxing of incoming media content to detect and block potentially malicious files before they reach devices. 5. Use endpoint detection and response (EDR) tools capable of monitoring anomalous behavior on mobile devices that could indicate exploitation attempts. 6. Restrict unnecessary network exposure of mobile devices and encourage use of VPNs and secure communication channels. 7. Regularly audit and review mobile device security policies to ensure compliance and readiness against emerging threats.