Source: The Great Interpretation of Dreams (Ibn Sirin)
A bear in a dream indicates a foolish man of great might, or a woman of bad character. Riding it indicates gaining a position or fear of a ruler.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
A bear indicates strife, evil, or a large, wicked man.
Source: Signs in the Science of Expressions (Ibn Shaheen)
A bear is interpreted as a strong, brave, foolish man, or a treacherous thief.