Cisco has introduced two new open-weight small language models (SLMs), Antares-350M and Antares-1B, designed specifically for identifying known vulnerabilities in existing codebases. These models are now available on Hugging Face, with access granted to vetted users, including academic institutions, nonprofit organizations, and security teams from public and smaller organizations.
The Antares models are part of Cisco's new Antares family of security SLMs, named after the red supergiant star. A key advantage of these models is their ability to run locally, ensuring that proprietary code remains within an organization's machines. This addresses privacy and compliance concerns associated with cloud-based large language models (LLMs) that send code to external servers for processing.
Cisco emphasizes that the Antares models are not chatbots but rather "investigators" or "search engines" specialized in vulnerability detection. This focused design allows them to efficiently locate specific security flaws, even within millions of lines of code. According to Cisco, the models were trained using a unique approach that enables them to employ multiple search strategies simultaneously.
The company claims that Antares-1B performs comparably to or better than several larger models in identifying security flaws. In Cisco's internal benchmark tests, Antares-1B reportedly outperforms Google’s Gemini 3 Pro and is on par with Z.ai's GLM-5.2. A future, unreleased model, Antares-3B, is said to surpass both GLM-5.2 and OpenAI’s GPT-5.5 in vulnerability detection.
Beyond performance, Cisco highlights the speed and cost-efficiency of its SLMs. The company states that Antares models can scan 500 code repositories in approximately 15 minutes, a task that frontier models might take five hours to complete. This efficiency translates to significantly lower operational costs, estimated at less than $1 per scan compared to $100-$150 for larger models.
While Antares-350M and Antares-1B are publicly available to vetted users, a larger 3-billion-parameter model in the Antares family, Antares-3B, will not be released to the public. Cisco intends to gate access to Antares-3B, ensuring its responsible distribution to specific communities that require it.
