The Secondary Resistances are
- Bleeding Resistance, reduces Bleeding Damage
- Vitality Resistance, reduces Vitality Damage, Vitality Decay Damage and Life Leech
- Energy Resistance, reduces Energy Leech Damage and Energy Burn
- Stun Resistance, reduces Stun duration
- Disruption Resistance, reduces Skill Disruption duration
For the hero, they are found on the second tab in the inventory. Unlike the Primary Resistances, the Secondary Resistances are not penalized in higher difficulties. However, the Anniversary Edition of the game does penalize Bleeding and Vitality Resistances on higher difficulties (-40%/-100% Epic/Legendary, respectively).