In Avast Antivirus before 19.4, a local administrator can trick the product into renaming arbitrary files by replacing the Logs\Update.log file with a symlink. The next time the product attempts to write to the log file, the target of the symlink is renamed. This defect can be exploited to rename a critical product file (e.g., AvastSvc.exe), causing the product to fail to start on the next system restart.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.4, requiring local system access to exploit with relatively low complexity without requiring user interaction . The vulnerability impacts integrity (unauthorized modifications), for affected systems. Impacting 1 product from avast organizations running these solutions should prioritize assessment and patching.
First disclosed in 2019, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.
2019-07-18T17:15:11.880
2024-11-21T04:20:46.377
Modified
CVSSv3.0: 4.4 (MEDIUM)
AV:L/AC:L/Au:N/C:N/I:P/A:P
3.9
4.9
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For avast's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.