Verizon Communications Inc. is considering either ending its takeover bid for Yahoo! Inc. or negotiating a price cut following news of another cyberattack at Yahoo, Bloomberg News reported Dec. 15, citing a source with knowledge of the matter.

While a Verizon team led by AOL Inc. CEO Tim Armstrong is still working on the integration planning, a separate team led by Verizon General Counsel Craig Silliman is reportedly reviewing the breach disclosures and the company's options. According to the report, the FBI is investigating the hack, while the New York Attorney General Eric Schneiderman is also looking into the matter.

Sen. Mark Warner, D-Va., called for an investigation into the latest Yahoo cyberattack that impacted more than 1 billion user accounts, Reuters reported Dec. 16. In a statement, Warner reportedly said he plans to "press the company on why its cyber defenses have been so weak as to have compromised over a billion users."

While Yahoo could not identify the intrusion associated with the theft, it believes this incident is different from the one it revealed in September. In that previously disclosed incident, data linked with at least 500 million user accounts were stolen from Yahoo's network in late 2014 by what the company deemed a "state-sponsored actor."