A new month is on the horizon, so what better time to look at making some new additions to your portfolio.

If exchange-traded funds (ETFs) take your fancy, then it could be worth looking at the five listed below. Here's what you need to know about these top funds:

BetaShares Global Cybersecurity ETF (ASX: HACK)

The first ASX ETF to look at in October is the BetaShares Global Cybersecurity ETF. It could be a great long term option given the very bright outlook for the global cybersecurity industry. Betashares notes that "an estimate of the total addressable market by McKinsey suggests that the cybersecurity market is $1.5-$2.0 trillion globally, and at best only 10% penetrated with a very long runway for growth." This bodes well for the companies held by the fund.

VanEck Vectors Morningstar Wide Moat ETF (ASX: MOAT)

The VanEck Vectors Morningstar Wide Moat ETF could be a great option in October. It is focused on investing in high-quality companies with fair valuations and sustainable competitive advantages. These are the qualities that Warren Buffett looks for when making investments. And following in Buffett's investment footsteps is never a bad idea given his impressive track record over multiple decades.

Vanguard MSCI Index International Shares ETF (ASX: VGS)

A third ASX ETF to buy in October could be the Vanguard MSCI Index International Shares ETF. It offers investors access to a portfolio of approximately 1,500 of the world's largest listed companies from major developed countries. Vanguard notes that this gives investors exposure to a diverse group of stocks that allow them to participate in the long-term growth potential of international economies.

BetaShares S&P/ASX Australian Technology ETF (ASX: ATEC)

The BetaShares S&P/ASX Australian Technology ETF could be another ASX ETF to buy in October. It was recently named as one to buy by the team at Betashares. The fund manager believes it could investors exposure to a side of the market likely to boom over the next decade. It said: "With the nascent adoption of AI, cloud computing, big data, automation, and the internet of things, there's a good chance that the next decade's major winners will come from the tech sector. Despite Australia's sharemarket skewing heavily towards financials and resources, investors can gain direct exposure to Aussie tech stocks via ATEC."

Betashares Global Cash Flow Kings ETF (ASX: CFLO)

Another ASX ETF that Betashares is recommending to investors is the Betashares Global Cash Flow Kings ETF. The fund manager notes that companies that generate high levels of free cash flow have historically tended to outperform the market over the medium to long term. As a result, this fund could be a top long term option for investors. It owns global companies with strong free cash flow such as Accenture (NYSE: ACN), Alphabet (NASDAQ: GOOG), and Visa (NYSE: V).