The report suggests that the company sold only 12 million Samsung Galaxy S5 units in the first three months after its launch, which if compared to its predecessor (the Galaxy S4), is 4 million less. The company overall sold nearly "40 percent fewer than projected".
The report further added that sales were down over 50 percent in China while the US market was the only "major market" for Samsung where an increase in sales figures were claimed.
Samsung is said to have overestimated demand for the Galaxy S5, which has led to a situation where the company is spending more on advertising to help move units which are piled up in its warehouses. A Samsung spokesperson, when contacted by The Verge declined to comment on the report and said, "We don't comment on rumours and speculation."
The figures are surprising considering that JK Shin, Head of Samsung's Mobile Business, claimed back in May that the company had shipped more than 11 million Galaxy S5 smartphones since its launch, which was said to be more than the 10 million Galaxy S4 units that sold in the same amount of time last year.
Top-level executive changes said to be under consideration include JK Shin "possibly ceding his role". However, the report adds that the plans are "far from final."
Samsung, at a recent Investor Forum, announced plans to slash the number of smartphone models it issues next year by up to a third.
Samsung also reported that its July-September quarterly profit was the lowest in more than three years, suggesting a decline in earnings from its smartphone business since 2011.