Vote buying is banned both in case of Parliamentary and Presidential elections.
Art. 69 - "2. Political parties which nominated their federal lists of candidates, such candidates, proxies and authorized financial agents of political parties and authorized financial agents of regional branches of political parties as well as other persons and organizations involved in election campaigns shall not bribe voters: they shall not give voters money, gifts and other things otherwise than for the performance of organizational work, signature collection, participation in the conduct of election campaigning; remunerate voters who perform the said organizational work depending on the results of the vote or promise such remuneration; sell goods at reduced prices; distribute free of charge any goods other than promotional materials specially produced for the election campaign and the cost of which does not exceed 100 rubles per unit; render services free of charge or at reduced rates. While conducting election campaigning candidates, political parties, electoral blocs, their authorized representatives and agents or other persons and organizations shall not influence voters by promises of money, securities, other things (in particular, depending on the voting results) and by rendering of services other than on the basis of decisions of bodies of state power, bodies of local self-government adopted in accordance with the legislation of the Russian Federation."
Source: Article 69 (2), Federal Law on Elections of Deputies to the State Duma of the Federal Assembly of the Russian Federation, 2014
Art. 56 - "(2) When holding election campaigns, candidates, their agents and authorized representatives for financial issues, political parties, their agents and authorized representatives as well as any other persons and organizations shall be forbidden to bribe voters: give them any money, gifts and other material values save as in consideration for any organizational activities (collection of voter signatures, campaigning activities), provide or promise to provide voters with any compensation for their organizational activities subject to the results of voting, sell goods at lower prices, distribute any goods free of charge, except for printed materials (including illustrated ones) and badges produced for the purposes of election campaigning, as well as provide any services free of charge or at lower prices. When holding election campaigns, candidates, their agents and authorized representatives for financial issues, political parties, their agents and authorized representatives as well as any other persons and organizations shall not be entitled to affect voters by promising them any money, securities or other material values (including subject to the results of voting) or by providing any services to voters otherwise than on the basis of the resolutions passed by government bodies and local authorities in accordance with the law of the Russian Federation."
Source: Articles 56 (2), Federal Law on the Presidential Elections in the Russian Federation, 2002