Nitrous acid behave as an oxidant as well as a reductant - why ?

Nitrous oxide

Compound that acts as oxidant as well as reductant

Although nitric acid acts only as an oxidising agent, nitrous acid acts both as an oxidising as well as a reducing agent- why ?

Why is nitrous acid oxidant as well as reductant ?

Nitrous acid acts as oxidant as well as reductant. Give suitable examples.