Edinburgh joined Cardiff at the top of Heineken Cup Pool Two after ending the Blues' unbeaten record.
Tim Visser's first-half try and a 14-point kicking haul from Greig Laidlaw earned Edinburgh a third win from four European matches to put them in with a chance of a first quarter-final appearance in eight years.
The January fixtures at home to London Irish and against Racing Metro in Paris will decide Edinburgh's fate following a comfortable success, albeit without scoring a second-half point. Dan Parks kicked three penalties for the Blues, who clinched a losing bonus point, which could prove crucial, when Leigh Halfpenny booted a 79th-minute penalty. London Irish are six points behind both sides ahead of their game with Racing Metro today.
The Blues opted to make Gavin Henson continue to wait for his debut, but their back line failed to flourish. Much of Edinburgh's good play came through Laidlaw, who gave Scotland head coach Andy Robinson food for thought up against international colleague Parks. Edinburgh were the more enterprising and expansive as they sought to avenge last week's 25-8 loss in Cardiff. The Blues trailed 6-0 after 11 minutes following two Laidlaw penalties before the Edinburgh captain sparked the move which led to the opening try.
Laidlaw found Nick De Luca with a short pass and the centre advanced into the Cardiff 22 before feeding Visser to crash over in the right corner. Laidlaw converted.After Parks responded with the Blues' first points, Edinburgh continued to pressure the visitors' line and Laidlaw punished the visitors' indiscipline.
The Edinburgh head coach, Michael Bradley, said: "After four matches we're joint top of the group. Hopefully that [the losing bonus point] won't be a key factor at the end of the pool."
Scorers: Edinburgh: Try Visser; Penalties Laidlaw 3 ; Conversions Laidlaw; Drop-goal Laidlaw. Cardiff Blues: Penalties Parks 3, Halfpenny.
Edinburgh: Paterson; Jones, De Luca, King (Scott, 73), Visser (T Brown, 74); Laidlaw, M Blai;, Jacobsen (Traynor, 79) Ford ( Lawrie, 73), Cross (G ilding, 64) Gilchrist ( Lozada, 79), Cox, Denton, Grant, Talei (Rennie, 70).
Cardiff Blues: Halfpenny; Evans, Laulala, Roberts, Czekaj (Hewitt, 40); Parks, L Williams; G Jenkins, T Thomas, Filise, B Davies, Tito, Paterson (Molitika, 49), Warburton, Rush. Referee: P Gauzere (France)