Here is a rough conversion from 2nd Ed AD&D with inspiration from the 3E version of the rat.
Hedgehog, CR 1/10 Tiny Animal; HD 1/4d8 (hp 1) Initiative +2 (Dex); Speed 10 ft; AC 15 (+2 Dex, +2 size, +1 natural); Attacks bite +4 melee; Damage bite 1d3-4; Face/Reach 21/2 ft by 21/2 ft/0 ft; SQ: Scent; SV: Fort +2, Ref +4, Will +1; Abilities: Str 3, Dex 14, Con 11, Int 2, Wis 12, Cha 4; AL N
Skills and Feats: Hide +10, Listen +6, Move Silently +6; Weapon finesse (bite)