Comment by wiskinator
15 hours ago
> Anthropic says Claude wrote the exploit "after initial prompting," that it runs "arbitrary commands as root, without any credentials or user interaction" on servers with a multipath TCP listener, and that in its proof of concept "it takes 48 minutes to leak a kernel pointer and another five minutes to reach the shell command execution."
This is wild. I'm a firmware nerd, not a backend nerd, what percentage of TCP/IP servers are 'multipath'?
Also, since IPv6 isn't affected, wouldn't it be funny if this is what it took to get everyone to switch.
> what percentage of TCP/IP servers are 'multipath'?
no idea, but at least Tailscale and Caddy were opening MPTCP sockets on servers I checked.
My understanding is that an app explicitly needs to open a "multipath" socket. Go 1.24 does that by default, so does Caddy, these would be the big ones.
Your understanding seems to be wrong.
Every Ubuntu version in the last decade is currently vulnerable.
https://ubuntu.com/security/CVE-2026-98432
Patches not yet available. That makes this a big deal.
This article says that this isn’t app level but is level and can be exploited before requests reach apps.
> on servers with a multipath TCP listener
I was talking about the Anthropic blog post, only Go/Caddy enable multipath TCP listeners by default.
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