CIBC World Markets cut its price target on the stock to $5.00 from $12.00, valuing BlackBerry at just $2.6 billion - the amount of cash it had on its books on Aug. 31.
At that price, the company is also worth nearly half the $4.7 billion that Fairfax Financial Holdings Ltd, BlackBerry's biggest shareholder, had offered to take the company private.
BlackBerry Ltd's shares were 4.4 percent higher at $6.78 in early trading on the Nasdaq.
The stock closed 16.4 percent lower on Monday after the company announced that it was no longer for sale and had appointed a new CEO to turn around the company.
"There will likely be some difficult decisions that will have to be made over the near term, including potential asset divestitures (i.e., hardware business) and restructuring," Paradigm Capital analyst Gabriel Leung wrote in a note.
Leung cut his price target on the stock by $3.50 to $7.00, with a "hold" recommendation.
BlackBerry Ltd said on Monday that instead of selling itself it would raise $1 billion by issuing convertible notes to a group of long-term investors.
"While the cash influx helps, we think an additional round of cost cuts is needed due to the rapidly deteriorating legacy services business and the rescaling of the hardware business," said Jefferies & Co analyst Peter Misek, who cut his price target to $6.00 from $8.00 while maintaining a "hold" rating.
BlackBerry Ltd once dominated the market for secure on-your-hip email but started losing the smartphone battle as Apple Inc's iPhone and devices using Google Inc's Android operating system slashed its market share.
"We suspect that the real problem is that things are going to get substantially worse before they start to improve," Societe Generale's Cross Asset Research said.
SocGen raised its rating on BlackBerry Ltd shares to "hold" from "sell," citing recent weakness in the share price. The brokerage maintained its $7.00 share price target.