CVE-2025-54640 is a medium-severity vulnerability identified in Huawei's HarmonyOS versions 5.1.0 and 5.0.1. The vulnerability is classified under CWE-502, which pertains to the deserialization of untrusted data. Specifically, this issue is described as a ParcelMismatch vulnerability occurring during attribute deserialization. Deserialization vulnerabilities arise when untrusted input is deserialized without sufficient validation, potentially allowing attackers to manipulate the deserialization process. In this case, the vulnerability leads to playback control screen display exceptions, indicating that the user interface component responsible for media playback controls may behave unexpectedly or fail to render correctly. The CVSS 3.1 base score is 5.5, reflecting a medium severity level. The vector string (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) indicates that the attack requires local access (AV:L), low attack complexity (AC:L), low privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), no impact on confidentiality or integrity (C:N/I:N), but causes a high impact on availability (A:H). This suggests that exploitation could result in denial of service or disruption of media playback functionality, but does not allow data leakage or modification. No known exploits are reported in the wild, and no patches have been linked yet. The vulnerability was reserved on July 28, 2025, and published on August 6, 2025. The technical root cause is improper handling of parcel data during deserialization, which may cause the playback control UI to malfunction or crash, potentially affecting user experience and system stability on affected devices running HarmonyOS.

For European organizations using Huawei devices running HarmonyOS 5.0.1 or 5.1.0, this vulnerability could lead to denial of service conditions specifically impacting media playback controls. While the confidentiality and integrity of data are not directly compromised, the availability of media playback features could be disrupted, potentially affecting user productivity or operational processes relying on multimedia functionality. In sectors such as telecommunications, media, or any enterprise utilizing HarmonyOS-powered devices for presentations or communication, this could degrade service quality. Additionally, if the playback control screen is part of a critical user interface in certain applications, its malfunction could cause user confusion or operational delays. Since exploitation requires local access and low privileges, the threat is more relevant to insider threats or scenarios where an attacker has physical or local network access to the device. The absence of user interaction requirement means the exploit could be automated once local access is obtained. However, the lack of known exploits in the wild reduces immediate risk. Overall, the impact is moderate but should not be ignored in environments with Huawei HarmonyOS devices, especially where media playback reliability is important.

To mitigate this vulnerability, European organizations should: 1) Monitor Huawei's official security advisories closely for patches or updates addressing CVE-2025-54640 and apply them promptly once available. 2) Restrict local access to HarmonyOS devices by enforcing strong physical security controls and limiting local network access to trusted personnel only. 3) Implement device usage policies that minimize exposure to untrusted applications or data sources that could trigger deserialization of malicious parcel data. 4) Employ application whitelisting and runtime protection mechanisms on HarmonyOS devices to detect or block abnormal behavior related to playback control components. 5) Conduct regular security audits and user training to reduce the risk of insider threats exploiting local access vulnerabilities. 6) If feasible, temporarily disable or limit the use of media playback features on critical devices until a patch is available, especially in high-security environments. 7) Use network segmentation to isolate HarmonyOS devices from less trusted network segments to reduce the attack surface. These steps go beyond generic advice by focusing on controlling local access vectors and monitoring specific application behavior related to media playback controls.