---
title: "Co-sign."
source_name: "Marc Andreessen 🇺🇸(@pmarca)"
original_url: "https://x.com/pmarca/status/2049920259432513702"
canonical_url: "https://www.traeai.com/articles/7afa458d-fbae-469c-8548-6fdd8ac7b49f"
content_type: "tweet"
language: "英文"
score: 4
tags: ["OpenAI","GPT-5.5-cyber","Mythos","自动化","网络安全"]
published_at: "2026-04-30T18:34:10+00:00"
created_at: "2026-05-01T01:31:31.491004+00:00"
---

# Co-sign.

Canonical URL: https://www.traeai.com/articles/7afa458d-fbae-469c-8548-6fdd8ac7b49f
Original source: https://x.com/pmarca/status/2049920259432513702

## Summary

Marc Andreessen 点赞 David Sacks 的推文，后者提及 OpenAI 的 GPT-5.5-cyber 模型在自动化网络安全任务方面取得进展，与 Mythos 类似。

## Key Takeaways

- David Sacks 强调了 Mythos 和 OpenAI GPT-5.5-cyber 在自动化网络任务上的能力。
- GPT-5.5-cyber 被视为能执行类似 Mythos 的自动化网络安全功能的新模型。
- 预计未来更多前沿模型（包括来自中国）将具备相似的自动化能力。

## Content

Title: Marc Andreessen 🇺🇸 on X: "Co-sign." / X

URL Source: http://x.com/pmarca/status/2049920259432513702

Markdown Content:
# Marc Andreessen 🇺🇸 on X: "Co-sign." / X

Don’t miss what’s happening

People on X are the first to know.

[Log in](http://x.com/login)

[Sign up](http://x.com/i/flow/signup)

# [](http://x.com/)

## Post

See new posts

# Conversation

[![Image 2](https://pbs.twimg.com/profile_images/1820716712234303489/9GpKDZjq_normal.jpg)](http://x.com/pmarca)

[Marc Andreessen ![Image 3: 🇺🇸](https://abs.twimg.com/emoji/v2/svg/1f1fa-1f1f8.svg) ![Image 4](https://pbs.twimg.com/profile_images/1919488160125616128/QAZXTMEj_bigger.png)](http://x.com/pmarca)

[@pmarca](http://x.com/pmarca)

Co-sign.

Quote

![Image 5](https://pbs.twimg.com/profile_images/1879600809693917185/GkBxdTd9_mini.jpg)

David Sacks

![Image 6](https://pbs.twimg.com/profile_images/1789812359084519424/hg3j0g2E_bigger.jpg)

@DavidSacks

·

7h

It’s time to demystify Mythos. Mythos is not magic. It’s not a doomsday device. It’s the first of many models that can automate cyber tasks (just like coding). OpenAI’s GPT-5.5-cyber can now do the same. And all the frontier models (including those from China) will be there x.com/aisecurityinst…

[6:34 PM · Apr 30, 2026](http://x.com/pmarca/status/2049920259432513702)

·

[171.4K Views](http://x.com/pmarca/status/2049920259432513702/analytics)

40

59

950

113

Read 40 replies

## New to X?

Sign up now to get your own personalized timeline!

Sign up with Apple

[Create account](http://x.com/i/flow/signup)

By signing up, you agree to the [Terms of Service](https://x.com/tos) and [Privacy Policy](https://x.com/privacy), including [Cookie Use.](https://help.x.com/rules-and-policies/twitter-cookies)

## Relevant people

*     [![Image 7](https://pbs.twimg.com/profile_images/1820716712234303489/9GpKDZjq_normal.jpg)](http://x.com/pmarca)       [Marc Andreessen ![Image 8: 🇺🇸](https://abs.twimg.com/emoji/v2/svg/1f1fa-1f1f8.svg) ![Image 9](https://pbs.twimg.com/profile_images/1919488160125616128/QAZXTMEj_bigger.png)](http://x.com/pmarca) [@pmarca](http://x.com/pmarca)    Follow   Click to Follow pmarca  You’re not talking to someone who woke up a loser. That loser attitude, that loser premise makes no sense to me.   
*     [![Image 10](https://pbs.twimg.com/profile_images/1879600809693917185/GkBxdTd9_normal.jpg)](http://x.com/DavidSacks)       [David Sacks ![Image 11](https://pbs.twimg.com/profile_images/1789812359084519424/hg3j0g2E_bigger.jpg)](http://x.com/DavidSacks) [@DavidSacks](http://x.com/DavidSacks)    Follow   Click to Follow DavidSacks  Tech founder & investor. Personal views only. Official account: [@davidsacks47](http://x.com/davidsacks47)    

# Trending now

## What’s happening

Only on X · Trending

#911onABC

Sports · Trending

Hector Borg

Trending in United States

Mikey McCoy

Sports · Trending

Tarasenko

[Show more](http://x.com/explore/tabs/for-you)

[Terms of Service](https://x.com/tos)

|

[Privacy Policy](https://x.com/privacy)

|

[Cookie Policy](https://support.x.com/articles/20170514)

|

[Accessibility](https://help.x.com/resources/accessibility)

|

[Ads info](https://business.x.com/en/help/troubleshooting/how-twitter-ads-work.html?ref=web-twc-ao-gbl-adsinfo&utm_source=twc&utm_medium=web&utm_campaign=ao&utm_content=adsinfo)

|

More

© 2026 X Corp.