# The best security AI is now gatekept — plan like you're not on the list

This spring AI crossed a line: Anthropic's Mythos found thousands of never-seen zero-days on its own, and OpenAI shipped a 'cyber' model that's more permissive for hacking-adjacent work. The same model that finds a thousand holes to fix them can find them to exploit them — so the labs put the best security models behind a velvet rope, open only to vetted partners and governments. That's defensible. It also means a vendor now decides who gets defended. Here's the honest read for everyone not on the list.

- **Author:** Fedor Chishchin
- **Published:** 2026-06-05
- **Tags:** security, business
- **Source:** https://fedorthinks.com/blog/gatekept-security-models

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This spring, AI quietly crossed a line in security. In April, Anthropic's Mythos —
a model built to autonomously find and fix vulnerabilities — turned up
[thousands of previously unknown zero-days](https://www.infosecurity-magazine.com/news-features/what-mythos-gptcybe-ai-mean-for/)
on its own, in an episode people started calling the "Vulnpocalypse." OpenAI
followed with
[GPT-5.5-Cyber](https://openai.com/index/gpt-5-5-with-trusted-access-for-cyber/),
a version of its flagship trained to be _more permissive_ on security work —
red teaming, penetration testing, exploit validation.

Here's the uncomfortable fact under all of it: the same model that finds a thousand
holes so you can patch them can find them so someone else can walk through them.
Defense and offense are the same capability. So the labs did something new — they
put the best security models behind a velvet rope.

## What "gatekept" actually means

GPT-5.5-Cyber and Mythos don't go to everyone. They go to _vetted_ partners.
OpenAI runs a
["Trusted Access for Cyber" program](https://openai.com/index/gpt-5-5-with-trusted-access-for-cyber/)
and just extended it to European governments, cyber agencies, and EU institutions;
Anthropic keeps Mythos even tighter, behind a partner program with a launch list
that includes the big security firms. If you're not on the list, you cannot have
the most capable defender. The cyber frontier is rented, not sold — and only to
approved tenants.

## Why that's defensible — and why it's uncomfortable

Both things are true, so hold them at once.

It's defensible: an autonomous exploit-finder in random hands is genuinely
dangerous, and you cannot open-source a tool that produces a thousand working
zero-days. Restricting it is the responsible-looking move.

It's also uncomfortable, because it means **a private company now decides who gets
defended well.** If machine-speed bug-finding is the new frontier of defense, and
only a curated list gets it, then everyone else — the small company, the
open-source maintainer, the hospital with no OpenAI contract — is defending with
last-generation tools. "Who is protected" just became a commercial decision made
by the same handful of companies that also sell the offensive capability. That's
not a conspiracy. It's just the shape of the market right now, and it's worth
saying out loud.

## And the rope leaks anyway

Here's the part that makes the velvet rope a false comfort: the capability spreads.
Experts warn that offshoots of these models will be
[plenty powerful enough to wreak havoc](https://broadbandbreakfast.com/gatekeeping-by-ai-frontier-labs-could-leave-critical-infrastructure-exposed/)
even if they're a step behind the frontier. So you end up with the worst possible
shape: the defenders are a club, the attackers are everyone, and the gap between
them is set by a vendor's partner list. I [wrote a week
ago](/blog/the-year-the-agent-became-the-attacker) about one amateur who breached
nine government agencies with off-the-shelf AI. That person was never going to be on
anyone's trusted-access list, and it didn't slow them down.

## The honest takeaway if you're not on the list (most of us)

Don't wait for the cavalry, because it probably isn't coming to you. Three things
follow:

- **Assume your attacker is already AI-augmented.** Not next year — now. Design
  your defense for an adversary who can find your bugs at machine speed, whether
  or not you can.
- **The boring defenses still decide the outcome.** The headline breaches of 2026
  fell to weak passwords and missing MFA, not exotic exploits. AI removed the
  _labor_ floor on attacks; it didn't break the locks. So the unglamorous basics
  matter more now, not less.
- **You don't need the gatekept model to play defense.** Open-weight security
  tooling trails the frontier by months but still finds the obvious holes faster
  than you will by hand — and it [runs on your own
  hardware](/blog/an-agent-in-every-laptop), where no one can gate it. The frontier
  cyber model is behind a rope; the 80%-as-good one is a download.

## The point

The cyber arms race got a new rule this spring: the best weapon is rented, not
sold, and only to approved tenants. If you're a government or a Fortune 100, you're
defended. If you're everyone else, the lesson isn't to lobby for a seat at the
table. It's that your safety can't depend on a partner list you're not on. Do the
unglamorous basics, assume the attacker has the AI you don't, and lean on the
very-good local tools nobody can gate. The cavalry isn't coming. Be your own.