Doppel’s AI defense system stops attacks before they spread

A single impersonation site can launch, target thousands of users, and vanish in under an hour. That’s more than enough time for an attacker to do real damage. And with generative tools, they can spin up hundreds more just like it.

Doppel was built to defend organizations from deepfakes and online impersonations, but quickly realized AI meant threats could scale infinitely. Attackers no longer needed to handcraft scams; they could generate endless variants of phishing kits, spoofed domains, and impersonation accounts in seconds.

“Damage from phishing attacks can happen within minutes as they spread across social media and messaging channels. The ability to generate infinite persuasion at almost no cost changed everything.”

—Rahul Madduluri, Co-founder and CTO, Doppel

Inside the rollout

To stay ahead, Doppel developed a new kind of social engineering defense system built on OpenAI GPT‑5 and o4-mini models. Doppel’s platform detects, classifies, and takes down threats autonomously, cutting analyst workloads by 80%, triples threat-handling capacity, and reduces response times from hours to minutes.

Staying ahead of infinitely faster threats

Traditional digital risk protection relied on humans to manually review impersonation sites, phishing domains, and social media profiles and posts. Doppel saw that model breaking down as attackers began to automate, launching threats faster, and across more surface areas, than humans could evaluate them.

“Our system processes a constant flood of signals to identify the real threats amongst the noise. Once a threat is detected, there is a very narrow window to act before the damage is done. Using AI to automate decision-making is one of the greatest unlocks for the company, allowing us to combat attacks at internet scale and speed.”

—Rahul Madduluri, Co-founder and CTO, Doppel

Orchestrating LLM-driven threat detection

Here’s how it works:

Training models through reinforcement fine-tuning (RFT)

—Kiran Arimilli, Software Engineer, Doppel