Yersinia implements several attacks for the following protocols: Spanning Tree (STP), Cisco Discovery (CDP), Dynamic Host Configuration (DHCP), Hot Standby Router (HSRP), Dynamic Trunking (DTP), 802.1q and VLAN Trunking (VTP), helping a pen-tester with different tasks.
You can download it from the following link: https://packetstormsecurity.com/files/download/40117/yersinia-0.5.5.1.tgz
Source: https://packetstormsecurity.com/files/40117/yersinia-0.5.5.1.tgz.html