Aug 18 (Reuters) - Canada's main stock index slipped for a fifth straight session on Wednesday, weighed down by mining stocks, while data showed annual inflation rate rose at its fastest pace since 2011.

The benchmark S&P/TSX composite index was down 12.48 points, or 0.06%, at 20,351.11 in morning trade, hovering near a two-week low hit on Tuesday.

The materials sector, which includes precious and base metals miners and fertilizer companies, shed 1.5%, as silver prices lost almost half a percent, and gold came under pressure.

Among the bright spots was luxury parka maker Canada Goose Holdings Inc, which climbed 4.9% on announcing a share repurchase program.

Numbers from Statistics Canada showed the country's annual inflation rate accelerated to a stronger-than-expected 3.7% in July, mostly driven by higher shelter costs.

However, consumer price index common, which the Bank of Canada calls the best gauge of the economy's underperformance, was 1.7%, below analyst expectations of 1.8%.

"As the Bank of Canada's preferred core measure remained unchanged at 1.7%, this report is unlikely to alter the path for monetary policy," said Candice Bangsund, portfolio manager for global asset allocation at Fiera Capital. "Policymakers have reiterated that the latest pricing pressures are likely to be transitory in nature."

Business jet maker Bombardier Inc rose almost 4% after a six-day losing streak, while the heavyweight financials sector inched up 0.1%.

BlackBerry Ltd gained 3.5% after U.S. brokerage Canaccord Genuity said it believed a cybersecurity flaw in a software designed by the company will have a minimal impact to its long-term prospects.

HIGHLIGHTS

* On the TSX, 79 issues advanced, while 147 issues declined for a 1.86-to-1 ratio to the downside, with 19.71 million shares traded.

* The TSX posted two new 52-week highs and four new lows.

* Across Canadian issues, there were 18 new 52-week highs and 19 new lows, with total volume of 39.06 million shares. (Reporting by Sruthi Shankar in Bengaluru)