n medium animal 

Perception +10; low-light vision, scent (imprecise) 60 feet

Skills Acrobatics +9 (+13 to Escape), Athletics +8, Stealth +9

Str +3 Dex +4 Con +3 Int -4 Wis +1 Cha +0

Lithe A weasel treats any tight space it can barely fit its head in or wider as difficult terrain and doesn't need to Squeeze to move through it.

AC  19; Fort +8, Ref +11, Will +6

HP 42

Speed 25 feet

Melee [>] jaws +11 (finesse), Damage 1d12+5 piercing plus Grab

Melee [>] claw +11 (agile, finesse), Damage 1d10+5 slashing

Constrict [>] 1d12+2 piercing, DC 20

Bestiary 3, page 291.