In the crystal structure of the title compound, C5H2N4, each molecule is linked by N-H...N[triple-bond]C hydrogen bonds to four other molecules, thus forming a network that can be described as a twofold interpenetrated three-connected three-dimensional (10,3)-net. The interpenetrated nets are related by (010) translation. If only intermolecular hydrogen bonds are taken into account, these nets can be considered as independent. However, the interactions between the cyano groups from different nets indicate mutual assistance of the two nets during their formation.