Twitter has warned of "extraordinary action" in China and Saudi Arabia, which is linked to a faulty aid speech.
The tip – found on November 15 and confirmed the next day – could have revealed the users' phone number country code or if their accounts were locked, the company said.
IP addresses from both countries had sent a large number of questionnaires on a form, Twitter said.
These could have been linked to "state sponsored operators," Twitter said.
Stressing that they could not confirm the "purpose or the granting of certain", Twitter reported that they had informed the authorities of their discovery "full transparency".
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For those who suffer immediately, has been reported, Twitter said. No full phone numbers were disclosed and no other personal information.
The company's share price fell by almost 7% on Monday.
News about the bug will come on the same day as the United States Senate released a report explaining how Russia used the impact of every social media platform in the 2016 election.
In particular, focusing on the targeting of conservatives on immigration, race and arms rights, the country also tried to weaken the vote of the left-wing African-American citizens by spreading false information about the electoral process.