Shares of Knight Capital, a trading firm where a software glitch in August caused dozens of stocks to fluctuate wildly, rose sharply Monday after a financial analyst upgraded the company.

Niamh Alexander of Keefe, Bruyette & Woods, upgraded the stock to a rating of "Market Perform" from "Underperform" and raised the price target to $2.60 from $2.25.

Alexander cited a report in The Wall Street Journal on Saturday that Knight Capital has been approached by at least two parties to buy part of its business, the so-called market-making division.

On Aug. 1, a technical glitch at Knight Capital flooded the stock market with unintended trades, causing stock prices to jump around. The trading losses threatened the company's survival, and Knight got a $400 million lifeline from a group of investors.

Knight Capital Group Inc. stock rose 25 cents, or 10 percent, to $2.74 in midday trading Monday. The stock has traded as high as $13.59 in the past year. It closed at $10.33 on July 31, the day before the glitch, and had fallen to $2.58 by Aug. 2.