Spartans Security Approved for Defense Access in Anthropic's Cyber Verification Program

We are pleased to share huge news. Spartans Security has been approved by Anthropic for Defense Access under its expanded Cyber Verification Program, which means our team can now use Claude Mythos 5.1, Claude Opus 5.5 and Claude Sonnet 5.5 for defensive cybersecurity work.

What the Cyber Verification Program is

Anthropic's Cyber Verification Program exists so that verified security teams can use its most capable models for legitimate cyber use cases. The program has now expanded to three access tiers, and every tier includes access to Anthropic latest and most capable module such as Claude Mythos 5.1. Our team now approved on Defense Access.

Why this is a huge deal for us

Defenders have always had to move quickly with limited time and limited people. Attackers do not wait for a business to finish its triage queue, and the time between a vulnerability being disclosed and being exploited keeps getting shorter. Access to more capable models gives our consultants another way to keep pace, without taking away the judgement and experience that clients actually hire us for.

Within the scope of Defense Access, we expect this to help us with the work we already do for clients:

• Triaging and verifying vulnerabilities faster, so the findings that matter get in front of the right people sooner
• Supporting malware analysis and reverse engineering during investigations
• Improving detection engineering, so the alerts our clients rely on are sharper and noisier ones are tuned out
• Supporting incident response, where the first hours count and clear thinking under pressure is everything

Output from work will be reviewed, vetted and validated by a our team regardless. The models help our team work faster and look wider. Anthropic or any other tools do not replace the human in the loop, it just make their work faster.

Using it responsibly

Access to models like this comes with real responsibility, and we take that seriously. As part of the program, Anthropic has asked verified organisations to follow its updated agent containment best practices, which set out how to use these models safely in security workflows. We are reviewing that guidance and building it into how our team operates. Our existing confidentiality and data handling commitments to clients do not change.

It also helps that Spartans Security is an approved CVE Numbering Authority (CNA). That means we already run a strict process to detect, manage and report security issues, and any issue found while using these models will sit under that same process, with strict controls and governance around it.

What this means for our clients

Since the release of Mythos and its cybersecurity capabilities, many Board members and senior executives have started to wonder whether their business is prepared to defend against attacks weaponised by AI tools like Mythos and other capable models. This is an important question, and every business should be asking from their IT/Technology department.

Providing our team the ability to leverage Mythos will allow us to answer it. We can help businesses understand the real risks of these AI enabled attacks and equip them to defend against them before they happen, not after. Alongside this, our penetration testing services continue to give you an independent view of how your environment stands up to real attack techniques.

If you work with us today, you do not need to do anything. You can expect the same team and the same standard of work, backed by better tooling behind the scenes. If you would like to understand how we are using AI safely within vCISO, incident response or security assurance engagements, we are always happy to talk it through.

Thank you to the Anthropic team for the approval, and to our own team for the work that put us in a position to earn it.

Want to talk about what this could mean for your organisation's defences? Get in touch with our team.