
Harley Quinn X |

To remove mummy rot, you need to be successfully hit with both a Remove Curse and Remove Disease within a minute of each other.
Quote from the Glossary section of the core rulebook, under Curses (you can use CTRL+F to help narrow it down):
Mummy RotType curse, disease, injury; Save Fortitude DC 16
Onset 1 minute; Frequency 1/day
Effect 1d6 Con damage and 1d6 Cha damage; Cure mummy rot can only be cured by successfully casting both remove curse and remove disease within 1 minute of each other.
In order to remove disease, you make a caster level check for both spells, and if it beats the DC of the mummy rot (16), then it's cured if both get off in one minute. Otherwise, it lingers on. Technically all you'd need to do is be able to cast the spell, which a 5th level cleric can do. So assuming lowest level, a level 5 cleric would need to roll and 11 on each spell. (Now of course there's the limiting factor of how many spells a cleric can cast per day, and how many attempts they can have fail in one day before they have to call it quits.)
For some officialness, see the links to Remove Curse and Remove Disease.