The detection of anomalies in time series is a critical task across various domains including time series generated by a diversity of distributed systems. Despite extensive research, no single algorithm is the undisputed leader in all respects. This paper introduces KDEAE, a novel unsupervised approach for univariate time series anomaly detection. This method combines autoencoders (AE) and kernel density estimation (KDE). The proposed approach segments time series into non-overlapping segments, encodes them using convolutional AE and constructs anomaly scores based on their density obtained from KDE. The method is evaluated on GutenTAG dataset collection using TimeEval framework and compared with 25 algorithms of the same category. The results show that KDEAE outperform 40% algorithms by ROC AUC and 60% by PR AUC scores and 60% by runtime. The paper concludes with suggestions for further research to enhance the method's performance and extend it to multivariate time series.