CVE-2025-53182 is a heap-based buffer overflow vulnerability identified in the PDF preview module of Huawei's HarmonyOS versions 5.0.1 and 5.1.0. The vulnerability is classified under CWE-122, which involves improper handling of memory buffers leading to overflow conditions. Specifically, this flaw arises due to a null pointer dereference scenario within the PDF preview functionality, which can cause the application or system function to become unstable or crash. The vulnerability requires no privileges (PR:N) and can be exploited remotely over the network (AV:N) with low attack complexity (AC:L). However, it requires user interaction (UI:R), such as opening a maliciously crafted PDF file, to trigger the overflow. The impact primarily affects availability (A:H), potentially causing denial of service by crashing the PDF preview module or related system components. There is no indication that confidentiality or integrity are compromised. No known exploits are currently reported in the wild, and no patches have been linked yet. Given the CVSS 3.1 score of 6.5 (medium severity), the vulnerability poses a moderate risk, mainly due to its potential to disrupt system stability rather than enabling code execution or data leakage.

For European organizations using Huawei HarmonyOS devices, particularly those relying on the PDF preview functionality, this vulnerability could lead to service interruptions or device instability. In sectors where availability and operational continuity are critical—such as finance, healthcare, and government—this could result in productivity loss or disruption of critical workflows. While the vulnerability does not directly compromise data confidentiality or integrity, denial of service conditions could indirectly affect business operations and user trust. Additionally, since exploitation requires user interaction, phishing or social engineering campaigns could be leveraged to trigger the vulnerability, increasing the risk in environments with less stringent user awareness or controls. The lack of known exploits currently limits immediate risk, but the absence of patches means the vulnerability remains open to future exploitation.

European organizations should implement targeted mitigations beyond generic advice. First, restrict or monitor the handling of PDF files on HarmonyOS devices, especially from untrusted sources, to reduce exposure to malicious documents. Employ network-level controls to detect and block suspicious PDF files or payloads. Enhance user awareness training focused on the risks of opening unsolicited or unexpected PDFs. Where possible, disable or limit the use of the PDF preview feature on HarmonyOS devices until a patch is available. Organizations should also establish monitoring for application crashes or abnormal behavior in the PDF preview module to detect potential exploitation attempts. Coordination with Huawei for timely patch deployment is critical once updates are released. Additionally, consider deploying endpoint protection solutions capable of detecting anomalous memory corruption behaviors associated with heap overflows.