Google has introduced Gemini 3.5 Flash Cyber, a lightweight AI model designed to improve cybersecurity by helping defenders identify, validate, and patch software vulnerabilities more efficiently. Built on Gemini 3.5 Flash and optimized for security tasks, Flash Cyber aims to deliver a cost-effective alternative to larger AI models while supporting large-scale vulnerability analysis.
The company said it has invested in cybersecurity research for years, including automated vulnerability discovery through CodeMender, its code security agent that can detect and fix critical software flaws. However, as AI systems become increasingly capable of discovering vulnerabilities faster than defenders can resolve them, Google believes a scalable and affordable approach is needed.
Gemini 3.5 Flash Cyber Focuses on Scalable Cybersecurity
According to Google, Gemini 3.5 Flash Cyber has been fine-tuned specifically to locate, verify, and remediate vulnerabilities more effectively than Gemini’s standard Flash models. Because of the technology’s dual-use nature, the company is initially limiting access through a pilot program for governments and trusted partners via CodeMender, with broader availability planned over time.
Google also confirmed that CodeMender’s core capabilities will be made available through generally available Gemini models on the Gemini Enterprise Agent Platform.
Flash Cyber Improves Large-scale Code Analysis
A major challenge in cybersecurity is exploring vast execution search spaces across complex codebases. Instead of relying on a single call to a large language model, CodeMender invokes Flash Cyber multiple times, allowing sub-agents to inspect significantly more code paths before generating one consolidated report.
Google said the model’s speed and lower operating cost make it suitable for continuous code scanning, software launch processes, and commit-scanning pipelines at scale.
Benchmark Results Show Competitive Performance
Google evaluated Gemini 3.5 Flash Cyber using the CyberGym benchmark, which measures AI agents against hundreds of real-world software vulnerabilities. Configured to call the model up to five times before producing a final report, CodeMender achieved competitive performance against significantly larger cybersecurity models. Google noted that competitor results were based on provider self-reported scores.
The model also outperformed Gemini 3.5 Flash and 3.6 Flash during Google’s internal Big Sleep evaluation, which tested vulnerability discovery in complex projects such as Chrome and Safari without safety guardrails.
In Chrome’s production commit-scanning pipeline, where vulnerabilities remained undisclosed to prevent benchmark contamination, Flash Cyber again delivered a significant improvement over Gemini 3.5 Flash. Google added that competitor models released after Opus 4.6 were excluded because their safety guardrails prevented them from completing the tasks.
Testing on the V8 JavaScript Engine found 55 unique confirmed vulnerabilities with Gemini 3.5 Flash Cyber, compared with 47 for Gemini 3.5 Flash and 36 for Opus 4.6, including 10 issues missed by both competing models.
Real-world Cybersecurity Deployment
Google said Flash Cyber is already helping secure internal projects, including Chrome, Android, Cloud, Ads and YouTube. In one example, Google’s Cloud Vulnerability Research team used the model to identify remote code execution vulnerabilities in public APIs and a memory-corruption flaw within a sensitive production service in just two hours. The model also generated a 100% reliable remote code execution exploit capable of bypassing Address Space Layout Randomization (ASLR) and Write XOR Execute (W^X).
Google added that early feedback from Wiz and Cloud CISO Security Engineering testers indicated a significant capability improvement over Gemini 3.5 Flash. The company also highlighted resources such as OSV.dev, which tracks more than 700,000 open-source vulnerabilities, and over a decade of OSS-Fuzz data as key training assets supporting its cybersecurity models.
