CVE-2025-20774 is a heap overflow vulnerability classified under CWE-122, affecting a broad range of MediaTek chipsets including MT2718, MT6739, MT6761, MT6765, MT6768, MT6781, MT6789, MT6833, MT6835, MT6853, MT6855, MT6877, MT6878, MT6879, MT6883, MT6885, MT6886, MT6889, MT6893, MT6895, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991, MT8196, MT8676, MT8678, MT8792, and MT8793. These chipsets are integrated into numerous Android devices running versions 14.0, 15.0, and 16.0. The vulnerability stems from a missing bounds check in the display subsystem, which allows an out-of-bounds write to heap memory. This memory corruption can be leveraged by an attacker who has already obtained System privileges on the device to escalate their privileges further, potentially gaining higher-level control over the device. Notably, exploitation does not require user interaction, which increases the risk of automated exploitation or silent attacks. While no public exploits have been reported yet, the vulnerability's presence in widely deployed chipsets makes it a significant concern. The issue was reserved in November 2024 and published in December 2025, with MediaTek acknowledging the flaw. No CVSS score has been assigned yet, and no official patch links are currently available, though a patch ID (ALPS10196993) and issue ID (MSV-4796) have been referenced. The vulnerability's exploitation requires prior System-level access, indicating it is not a remote code execution vulnerability but rather a local privilege escalation vector that could be chained with other exploits for full device compromise.

For European organizations, the impact of CVE-2025-20774 is primarily on the security and integrity of mobile devices that use affected MediaTek chipsets. Since these chipsets are common in many consumer and enterprise Android devices, the vulnerability could allow attackers who have already compromised a device at the System level to escalate privileges further, potentially gaining root or kernel-level access. This could lead to unauthorized access to sensitive corporate data, interception of communications, installation of persistent malware, or bypassing of security controls. The lack of user interaction needed for exploitation increases the risk of stealthy attacks, making detection more difficult. Organizations with Bring Your Own Device (BYOD) policies or those deploying MediaTek-based devices in critical roles may face increased risk of insider threats or targeted attacks. Additionally, the vulnerability could be exploited in multi-stage attacks where initial access is gained through other means, then leveraged to deepen control over the device. The absence of known exploits currently limits immediate risk, but the broad device footprint and potential severity necessitate proactive mitigation. The impact on availability is limited but could arise if exploitation leads to device crashes or instability.

To mitigate CVE-2025-20774, European organizations should: 1) Monitor MediaTek and device vendor advisories closely for the release of official patches corresponding to patch ID ALPS10196993 and apply them promptly across all affected devices. 2) Implement strict device management policies that limit System-level access to trusted applications and users only, reducing the likelihood of an attacker obtaining the prerequisite privileges for exploitation. 3) Employ mobile threat defense solutions capable of detecting anomalous behavior indicative of privilege escalation attempts or heap corruption exploits. 4) Enforce application whitelisting and sandboxing to minimize the attack surface and prevent unauthorized code execution. 5) Educate users and administrators on the risks of privilege escalation vulnerabilities and encourage reporting of unusual device behavior. 6) For organizations with BYOD policies, consider restricting or isolating devices with vulnerable chipsets until patched. 7) Conduct regular security audits and penetration testing focused on mobile device security to identify potential exploitation chains involving this vulnerability. 8) Collaborate with device manufacturers and carriers to ensure timely updates and security support for affected devices.