Submitted by elprofesor
Update periods in TWAP oracles reflect risk of an asset.  Updating more frequently accurately prices an asset but increases capabilities of manipulation (which should be harder with more stable assets), whereas longer update periods prevent manipulation but does not accurately price assets (due to the time difference between updates). Volatility of an asset should be considered when calculating update periods. However, in Vaders TwapOracle.sol no such considerations are made, the _updatePeriod cannot be changed after deployment of the contract. Additionally, each asset uses the same _updatePeriod  which does not adequately account for the differences in risk for each asset. This could lead to price manipulation or inadequate pricing of assets.
the only chance to set _updatePeriod
_updatePeriod used in time elapsed calculation
Add the following function
CloudEllie (organizer) commented:
SamSteinGG (Vader) diagreed with severity:
alcueca (judge) commented:
SamSteinGG (Vader) commented:
