I cannot overstate how powerful codex is for cybersecurity work.
I'd encourage all defenders to sign up for Trusted Access for Cyber (https://t.co/e1Mh8aZArY) and give it a shot for their workflows.
If orgs are slow to get TAC approvals, please reach out to me.
Our statement on the UK government’s demand that all content on all devices sold or used in the country be scanned, on the presumption of nudity, using a dystopian combination of age verification and content scanning. This proposal will not safeguard children. It endangers us all.
https://t.co/VdWe9uhi8p
Watching Codex use a Mac that’s fully locked feels slightly impossible the first time you see it.
Apple built trusted foundations on macOS for this years ago. Codex is now shipping something magical on top of them!
Introducing Daybreak: frontier AI for cyber defenders.
Daybreak brings together the most capable OpenAI models, Codex, and our security partners to accelerate cyber defense and continuously secure software.
A step toward a future where security teams can move at the speed defense demands.
The security industry is entering a period of compression. Model cybersecurity capabilities are rapidly increasing, and it's critical we arm defenders with the tools they need to protect what matters most.
We're launching two models today:
GPT-5.5 with TAC (Trusted Access for Cyber)
GPT-5.5-Cyber (Limited Preview)
GPT-5.5 is our starting point for most defensive workflows. It's exceedingly good at cybersecurity workflows and tasks like secure code review, vulnerability triage, detection engineering, malware analysis, and patch validation. We think this model is the right starting place for most organizations.
GPT-5.5-Cyber is exceptional for authorized workflows, including red teaming, penetration testing, and controlled validation. It's in research preview for specific organizations and requires enhanced verification and account-level controls.
We expect to continue to accelerate defenders with various models, including both our flagship models through Trusted Access for Cyber, and with dedicated cyber models like GPT‑5.5‑Cyber and even more cyber-capable models in the future.
https://t.co/2QWDkKLMBS
Codex can now take on more of your browser dev work.
With the new Chrome plugin in the Codex app, it can test web apps, gather context across tabs, use web DevTools efficiently in parallel, and keep results organized without taking over your browser.
we're starting rollout of GPT-5.5-Cyber, a frontier cybersecurity model, to critical cyber defenders in the next few days.
we will work with the entire ecosystem and the government to figure out trusted access for cyber; we want to rapidly help secure companies/infrastructure.
Don't just reset Codex rate limits for fun, it costs money.
Don't just reset Codex rate limits for fun, it costs money.
... but the vibes are good ...
I have reset Codex rate limits for ALL paid plans to celebrate a good week and allow everyone to build more with GPT-5.5. Enjoy
The way I talk to Codex and what tasks I can give it has drastically changed in the last few weeks. I worry less about which context I need to give Codex.
Wrote up some of the ways I work now 👇
We’re expanding Trusted Access for Cyber with additional tiers for authenticated cybersecurity defenders.
Customers in the highest tiers can request access to GPT-5.4-Cyber, a version of GPT-5.4 fine-tuned for cybersecurity use cases, enabling more advanced defensive workflows.
https://t.co/RMMXQklFar
Three million people are now using Codex weekly - up from two million a little under a month ago. Incredible to see the growth. Thank you to all of you and to the ecosystem we’re part of. To celebrate, we’re resetting rate limits so you can keep building, and we’ll reset them every additional 1M users until we reach 10M, so we can keep celebrating along the way.
Enjoy and thank you!
On 29 April, we’re bringing together the most ambitious builders for Australia’s first Codex Hackathon 🇦🇺
Build something in a single afternoon that wouldn’t be possible without Codex.
~$200K USD in credits & subscriptions up for grabs.
We’ll bring the tokens and vibes ✨ - see you there.
Link below 👇
Subagents are now available in Codex.
You can accelerate your workflow by spinning up specialized agents to:
• Keep your main context window clean
• Tackle different parts of a task in parallel
• Steer individual agents as work unfolds
The Codex app is now live on Windows.
The app runs both natively and in WSL, with integrated terminals for PowerShell, Command Prompt, Git Bash, or WSL.
We also built the first Windows-native agent sandbox — using OS-level controls to block filesystem writes outside your working folder and prevent outbound network access unless you explicitly approve it.
Plus: 7 new “Open in …” apps and 2 new Windows skills (WinUI + https://t.co/r7nDJ6PFcc).
Try it and tell us what you think.
Building malware analysis lab
A step by step guide for building local analysis lab at home.
A post by David Varghese.
Source: https://t.co/EynE7WSkzZ
#redteam#blueteam#maldev#malwaredevelopment
Over the weekend I compiled all my past blog posts and research into a roadmap/compendium for people looking to learn more about hardware reverse engineering.
Check it out here:
https://t.co/V883lp4kXo
After Months of Development, FINALLY ready to share: Harden System Security🎉
✅ Complete System Hardening
✅ Security Posture Analysis
✅ All-in-One Toolkit
✅ Built-in Intune support for Scalability
✅ Beautiful Modern UI
✅ CLI support
https://t.co/lfd3SaDvvM
#Cyber#Windows