The Federation Council passed a draft measure that would increase fines from $6,000 to $16,000 and include a possible prison sentence of four years for the dissemination or the illegal seizure of information classified as secret, state-run news agency RIA Novosti reports.
The measure would need the signature of President Vladimir Putin to become law. The measure expands the reach of treason legislation to include international organizations.
Putin has faced tough criticism for his crackdown on opposition voices following his election to a third non-consecutive term this year.
RIA Novosti reports that the bill sparked public controversy as it passed through the State Duma as critics said it was ripe for abuse.
Victoria Nuland, a spokeswoman for the U.S. State Department, has said Washington had serious concerns about the treatment of opposition activists in Russia.
Leonid Razvozzhayev, a supporter of the opposition Left Front movement, said he was abused by Russian authorities after getting arrested in Ukraine on charges of supporting Putin's ouster.