Net income rose by 32% to 762m francs (Â£498m) in the third quarter, below analyst forecasts for 804m francs.
UBS is in talks with authorities to settle allegations that it colluded in manipulating key rates in the $5.3tn-a-day foreign exchange market.
However, it has yet to reach a deal.
Both UK and US regulators are also said to be investigating other lenders, including JPMorgan and Barclays.
"We are actively addressing litigation and regulatory matters," UBS chief executive Sergio Ermotti said in the bank's quarterly report.
UBS also said it expected legal and regulatory charges to remain "elevated for the foreseeable future" because of the "current regulatory and political climate affecting financial institutions".
The Swiss bank had warned last month it could face "material monetary penalties" because of the currency-rigging investigation.
It has already paid about $3.6bn in penalties since 2012. Among other things, it has been accused of helping wealthy clients avoid taxes.
UBS shares traded in Zurich have lost nearly 9% of their value this year.
Switzerland's biggest bank, UBS, has missed profit estimates after it set aside $1.9bn (Â£1.2bn) in legal provisions amid an investigation over alleged currency-rigging.