Submitted by berndartmueller, also found by minhquanym
All funds can be migrated (withdrawn) at once to the caller vault by using the BaseStrategy.withdrawToVault function which internally calls MyStrategy._withdrawAll.
The latter function has the following check in place:
MyStrategy.sol#L184-L187
Funds can only be withdrawn (migrated) if the balance in LOCKER is fully unlocked.
By locking a small amount of want tokens via AuraLocker.lock with the strategy address, a malicious individual can cause DoS and prevent withdrawing and migrating funds to the vault.
The following test case will replicate the DoS attack by locking dust want tokens for the strategy address. This causes vault.withdrawToVault to revert.
Call LOCKER.processExpiredLocks(false); in MyStrategy._withdrawAll directly and remove the check which enforces unlocking all want tokens on L184-L187.
Alex the Entreprenerd (BadgerDAO) confirmed and commented:
Alex the Entreprenerd (BadgerDAO) disagreed with severity and commented:
jack-the-pug (judge) validated and decreased severity to Medium
Alex the Entreprenerd (BadgerDAO) commented:
For this contest, 35 reports were submitted by wardens detailing low risk and non-critical issues. The report highlighted below by IllIllI received the top score from the judge.
The following wardens also submitted reports: sorrynotsorry, Tadashi, unforgiven, 0xNazgul, defsec, reassor, oyc_109, Chom, Meera, robee, joestakey, codexploder, minhquanym, 0xFar5eer, 0xNineDec, a12jmx, hyh, saian, zzzitron, 242, asutorufos, cryptphi, Czar102, Funen, GimelSec, gzeon, Picodes, Sm4rty, TerrierLover, Waze, _Adam, 0v3rf10w, 0x1f8b, and 0xDjango.
