The hackers who seized control of the Twitter accounts of Joe Biden, Kim Kardashian, Barack Obama and Elon Musk appear to have been in it only for the money.
But with social media now the main way many politicians, countries and companies communicate with the public, U.S. lawmakers were wondering if it could have been worse.
"While this scheme appears financially motivated...imagine if these bad actors had a different intent to use powerful voices to spread disinformation to potentially interfere with our elections, disrupt the stock market, or upset our international relations," U.S. Senator Ed Markey, a Democrat, said in a statement.
Twitter Inc said hackers had targeted employees with access to its internal systems and "used this access to take control of many highly-visible (including verified) accounts and Tweet on their behalf".
Other high-profile accounts that were hacked included rapper Kanye West, Amazon founder Jeff Bezos, investor Warren Buffett, Microsoft Corp co-founder Bill Gates, and the corporate accounts for Uber and Apple Inc.
Twitter's shares slid after the hack, trading nearly 2 percent lower late on Thursday morning after paring earlier losses. In an extraordinary step, it temporarily prevented many verified accounts from publishing messages as it investigated the breach.
The hijacked accounts tweeted out messages telling users to send bitcoin and their money would be doubled. Publicly available blockchain records show that the apparent scammers received more than $100,000 worth of cryptocurrency.
CEO Jack Dorsey said in a tweet on Wednesday that it was a "tough day" for everyone at Twitter and pledged to share "everything we can when we have a more complete understanding of exactly what happened".
But the breach is certain to refocus attention in Washington on social media companies, which have already attracted the concern of critics on both the left and the right because of their vast reach, security and privacy policies, and impact on political discourse.
"A successful attack on your system's servers represents a threat to all of your users' privacy and data security," Republican Senator Josh Hawley wrote in a letter to Dorsey.
Frank Pallone, a Democrat who chairs the House Energy and Commerce Committee that oversees a sizeable portion of U.S. tech policy, said in a tweet the company "needs to explain how all of these prominent accounts were hacked."
Financial analysts said hacks of this nature are not likely to have much material impact on Twitter's balance sheet, although it could lead the company to spend more on security.
The hack "certainly doesn't help," Joe Wittine, Edgewater Research analyst, told Reuters in an email. It will pose more of a "reputational risk", versus "material near-term risk to advertising revenues."
Bernstein analyst Mark Shmulik said in the long-term, "maybe if a few of the 'blue check mark' accounts decide to leave the platform that could have a minor impact on usage."
