Slightly more technical information from Wired: https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/
TL;DR: Remote Code Execution via RDP on all windows versions, including 7 and 10.
> "Microsoft today warned Windows users of seven new vulnerabilities in Windows that, like BlueKeep, can be exploited via RDP, a tool that lets administrators connect to other computers in a network. Of those seven bugs, Microsoft's advisory emphasized that two are particularly serious; like BlueKeep, they could be used to code an automated worm that jumps from machine to machine, potentially infecting millions of computers."
> "Unlike BlueKeep, however, the new bugs—half-jokingly named DejaBlue by security researchers tracking it—don't merely affect Windows 7 and earlier, as the earlier RDP vulnerability did. Instead, it affects Windows 7 and beyond, including all recent versions of the operating system."
I imagine the type of people who have RDP publicly exposed are the same type of people who will not be upgrading from Win7 anytime soon.
I suspect we will see many exploits of this to come.
They can release it on the same day as the regular updates, and scan the whole IPv4 address space every hour.
That way, the pool of unpatched machines will be so tiny it isn't worth evil people trying to exploit it.
A quick Shodan query already does what you're thinking.
To quote the CVE:
> Disable Remote Desktop Services if they are not required.
> Block TCP port 3389 at the enterprise perimeter firewall
If you're using a VPN or RD Gateway which have been best practice for tens of years, you're already insulated. I'd still patch but outside of business hours.
To make matters worse I can't even run Windows updates on my laptop because the IT department has blocked it. I can only run updates at home.
It isn't as secure as a VPN (and not as convenient), but definitely a stop-gap if you don't want to pay for Client VPN.
On the contrary, most critical software is plenty new - things like MS Office. Still bound to Windows.
The remaining systems rely on truly custom software and should be either airgapped (so no RDP) or rewritten. I'm thinking industrial - they should've planned for this many years beforehand.
There were instances back when Windows XP was the main driver.
But sure, I suppose, that niche edge case (local context without local code execution) could hypothetically exist somewhere, but patching this won't make you secure.
A simple virus could even do it. It takes only one instance for this bug to completely take over your network if you're Windows based. Remember Windows XP time? That's how it is.
Unless you completely cut off internal network everywhere. Good luck with that policy.
You wouldn't even know you have been owned completely and expect only a router issue if the breach is from there. Or not even spot anything out of ordinary.
About the only real way is to presume internal network is compromised and keep diversity and backups to reduce impact.
Compartmentalize, do not centralize, no matter how much money you'd save that way. If a man has to go to fix an issue instead of remote login, so be it.
And yes, security is a layered approach. That's why we recognize that the internet isn't the only threat vector out there.
Edit: Why wouldn't you patch internal servers for this anyway? Let's say there is an existing threat with code execution like you say. Now he can trivially access all machines on the network because they share a common vulnerability. At least make him work for it.
Then I'm in real trouble with or without this. A compromised device can sniff the network, masquerade, inject network traffic (inc. DNS), and can attack every other device on that same segment.
> I don't need code execution from an existing internal resource.
If you cannot execute code in an internal context then you cannot exploit this bug, you'd effectively be an external attacker. Your own example had you running code on a locally connected "BYOD" device. Therefore you're already executing code in that context.
> Why wouldn't you patch internal servers for this anyway?
Nobody suggested that. In fact quite to the contrary.
By the way while we're discussing niche edge cases, what's your strategy to protect against Van Eck phreaking? Seems about as concrete as the attack vector you're proposing (local network access with no way to execute code).
"If they're attacking you from an internal vector they likely already have code execution within that internal context, making this bug largely redundant."
I was disagreeing that this is redundant. This vulnerability is a remote code exploit that could give an attacker control over the target just by sending a specially crafted packet. It is not some Apache misconfiguration affecting a couple servers, it's baked into all versions of Windows.
They were testing it for corporate users...
I would also be willing to bet that the majority of people who have it "disabled" are still sending back plenty of Telemetry. If you really care, your best option is to just not use Windows.
* Set off a crash loop in connection with my setup that had been pretty conservatively setup. It was fixable, but a nonsense problem to deal with.