Fable Security launches with $31m to tackle human risk in cybersecurity

Fable Security, a new human risk management platform, has launched with $31 million in funding from Greylock Partners and Redpoint Ventures. It is already working with enterprises across finance, healthcare, logistics, and technology, helping security teams reduce employee-driven risk with targeted, real-time interventions.

Fable was founded by Nicole Jiang and Dr. Sanny Liao, both early team members at Abnormal AI. At that company, they helped build and scale behavioral-based security products and saw firsthand how the threat landscape was shifting.

SEE ALSO: UpDownTool lets you move from Windows 11 to Windows 10 in just 5 clicks -- without losing any data

According to the founders, traditional training no longer keeps up with the speed and complexity of modern attacks.

“Companies spend billions on cybersecurity, but human risk is still the biggest unsolved problem that every security team wants to fix,” said Nicole Jiang, co-founder and CEO of Fable Security. “One-size-fits-all security awareness programs with generic training modules and phishing simulations do little to actually reduce risk. They are unable to handle the volume, speed, or sophistication of AI threats that exist today. Fable is here to change this paradigm, with a platform purpose-built to tackle the full spectrum of risky employee behaviors at scale.”

AI's security threat

Fable is designed to intervene where traditional tools fail. Jiang and Liao were particularly concerned about the rise in AI-enabled attacks.

In the past year alone, phishing attacks generated by AI rose by 60 percent, and vishing surged by 442 percent, often driven by deepfake audio impersonating trusted individuals.

“Human driven risk remains one of the biggest challenges in cybersecurity as missteps can create direct pathways for malicious attacks,” said Arvin Bansal, veteran Fortune 100 CISO. “As AI-powered threats evolve, we need AI-driven training to keep pace. Platforms like Fable deliver targeted, adaptive education that meets employees where they are, tracks engagement, and evolves with real-time feedback. That kind of precision is essential to reducing human risk across a large, diverse workforce.”

Fable’s approach focuses on changing behavior with precision. At the core of its platform is the Human Behavior Index, a proprietary system that collects real-time signals from identity, access, cloud, endpoint, and productivity systems. These signals help pinpoint employee actions that introduce risk.

Fable then uses those insights to generate targeted interventions -- videos, nudges, two-way chat prompts, or automated workflows -- delivered in apps like Slack and email, exactly where employees work.

These interventions are personalized by role, behavior, and access level, and timed to moments of heightened risk. Fable’s model avoids unnecessary training, instead focusing on risk-aware prompts that aim to reshape employee behavior at scale.

Cyrus Tibbs, CISO at Pennymac, shared the results of an internal test. “We chose Fable because its personalized approach to security awareness led to more effective and faster employee behavior change.”

He added that the company saw “a 13x faster behavior change during an A/B test after deploying a personalized Fable intervention versus a generic briefing.”

Since launching with its first customer less than a year ago, Fable has already helped enterprises like Pennymac, Genesys, and the Democratic National Committee. According to the company, customers have reduced phishing clicks by more than 85 percent, lowered PII exposures by 60 percent, and doubled employee engagement with post-training content. More than 40 percent of employees skipped unnecessary training, saving time while still reducing risk.

“In the AI era, attackers can now target people with unprecedented precision and effectiveness, making the human layer the most vulnerable layer in security,” said Saam Motamedi, General Partner at Greylock Partners. “Fable addresses this head-on by reshaping human behavior with real-time, intelligent interventions. Nicole and Sanny have a distinguished track record of building innovative behavioral AI security products and are redefining the human risk management market at Fable Security.”

Fable began inside Greylock Edge, the firm’s venture studio, and raised its seed round from Greylock, which has incubated and backed companies like Abnormal AI, Palo Alto Networks, Okta, and Wiz.

Redpoint Ventures led the Series A round. The firm has also backed security startups like Cyera and Chainguard.

Erica Brescia, Managing Director at Redpoint Ventures, said, “Security awareness training has become a checkbox -- ineffective, outdated, and blind to how people actually behave. Fable is the first company I’ve seen that throws out the playbook of a failing category. They’re building what modern security teams truly need: visibility into human risk, tools to actually change behavior, and AI that moves at the speed of attackers.”

The Fable team includes cybersecurity and behavioral science experts from companies like Abnormal AI, Microsoft, Palantir, and Palo Alto Networks.

Jiang and Liao believe their combination of AI, behavior design, and real-time delivery positions Fable to offer a new kind of defense, one focused on people, not just machines.

What do you think about Fable’s approach to real-time behavior-based security? Let us know in the comments.