Rising food prices made a large contribution to the change, with an increase of 0.8% between August and September 2017, compared to a 0.4% fall last year.
It comes as analysis by the Institute for Fiscal Studies has found the benefits freeze is expected to leave over 10 million families an average of £450 a year worse off in real terms by 2020.
Liberal Democrat Leader Vince Cable commented:
“The Brexit squeeze caused by the falling pound is getting worse, and it is hitting the poorest families hardest.
“This above-target inflation is increasing the cost of the weekly shop and cutting into people’s living standards.
“The Chancellor must end the benefits freeze that is set to leave millions of families hundreds of pounds poorer a year.
“Above all, the government must change course from a destructive Brexit that would damage living standards and push up prices further.”