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"An unauthenticated attacker could exploit this vulnerability by sending a specially crafted packet to an affected service over the network. Successful exploitation could allow the attacker to execute code on the target system. No authentication or user interaction is required.."

Still, the question remains... How?

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It mentions that it may rely on other services or security measures running- I wonder if there’s something like this hitting a firewall or av and then that calling out to paint to check file type or size out something like that?
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It still makes it sound like the problem really is the other service that is letting a remote connection invoke some part of MS paint.
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But why MS Paint? What functionality does it offer to another program to get called on specifically? And if this other service isn't calling on it specifically, what else can it be tricked into calling? And how many of those are also vulnerable to being stabbed in the back? The smaller interior holes are a problem, sure, but it seems like the CVE should be for the hull hole in that case.
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Sounds like they just mean opening a file that you got from somewhere else.

>The CVSS score of 8.1 marks this as a high‑severity RCE. The EPSS score is not available, and the vulnerability is not listed in CISA’s KEV catalog. Based on the description, the likely attack vector is remote: an attacker can deliver the malicious file over a network connection, for example via Remote Desktop, file shares, or other network‑exposed services that allow users to open images. The lack of EPSS data does not diminish the threat posed by a known RCE, but it does make precise likelihood estimation difficult.

https://app.opencve.io/cve/CVE-2026-83844

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That's... that's not RCE though.
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Yes, it is.
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Sounds like it might be automatically opening a file that was sent over the network without any user interaction.
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Reading tea leaves is still reading tea leaves, even if you make an AI do it… (which is what this is, judging by other things I've seen on opencve.io)
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Yeah, OpenCVE also includes this:

> After applying the update, verify that the target Windows systems are running a version that includes the CVE fix before disabling legacy file‑open processing in Paint.

Which is complete nonsense. "Legacy file-open processing" isn't a real configurable option in Paint and this seems to suggest that enabling it is some sort of mitigation. The resolution is simply to update Paint.

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The direct implication is that current generations of ms paint are a “service over the network.” Probably a theoretically possible RPC end point of svchost.exe
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I'm thankfully out of the loop on Windows these days, but as I remember it Paint did not have any network features? Is that still true? If if is, maybe it is a misfiling of the CVE and it isn't remote?

Or are they chaining a browser auto opening a download in paint, (but browsers shouldn't do that)...

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If they know what you paint/edit, they can sell you ads better
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These days paint has copilot...
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Why for the love of everything that is good does MS Paint have network trash in it. It's a super simple bitmap editor. Like Notepad, it's simple and just works.

Make a new product and bundle that as an option if you want to drastically change the functionality.

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Hate to break it to you..

> Notepad in Windows includes AI features powered by Copilot that help refine and shorten text with the assistance of GPT. By default, these AI features are enabled on managed devices

https://learn.microsoft.com/en-us/windows/client-management/...

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> Like Notepad, it's simple and just works.

I mean… what else were the people working on Notepad and Paint to do!?

The order came down to integrate AI, and they wanted to be promoted.

Every single day I’m happier and happier than I use Linux now.

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Some distro will default to integrating an AI into bash any day now. It's only a matter of time till less and vim have AI search.
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There are certainly many options to choose from: https://gist.github.com/ColinKennedy/8a0eea1b18b6e22bc10daa6...
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Luckily with OSS we can fork it
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This is the only network feature paint has iirc, so that's probably it.
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It's the only network feature I can think of, but what is it doing opening a port to wait and listen for anything?
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I wonder if it could be through a file:// or some deeplink custom url handler that opens in Paint and clicking on it with some carefully crafted file path could make it read out of bounds (since that's the associated weakness reported) and execute something.
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Whatever it is, it doesn't require any clicking or user interaction. Maybe my imagination is just limited but I can't imagine why Paint is making itself available for incoming traffic on the network.
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Ah, no interaction. Yikes, doesn't make sense Paint would have a server tho.

Should be easy to verify for someone with a windows machine if it does.

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Mine doesn't have a mouse or keyboard at the moment, so I'm only checking over an SSH->WSL connection. But it sure doesn't look like it's opening any ports from here.

So I guess either some random OS component is listening to the network and just-as-inexplicably asking Paint to do something for it. Or one of Paint's outbound connections is vulnerable if hijacked by a mitm. Network interception's one of the examples used for the "High" Attack Complexity rating that MS gave this CVE. Maybe powered by eMudhra for any systems that haven't revoked those certs? That'd be topical.

But still wouldn't really make sense. A patch for machines that are actively updating Paint but dodging cert revocations? Nothing really makes sense about this silly Paint CVE.

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Maybe because a .bmp file could be sent remotely.

Or maybe after the .bmp file is executed, it can install something that opens an outbound TCP connection to its C2, and thus can receive commands. Would not need admin privileges because it doesn't open a port, just 'outbound' connections, like a long-poll.

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Sending a BMP file that the user has to open doesn't match what little published details we have:

> The vulnerable system can be exploited without any interaction from any user.

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you are right, it seems like the latter outbouns tcp connection is already being opened by paint, and that is what is exploitable.

since it exposes no port, I’d assume it isn’t trivial to exploit, paint will chose its target (a microsoft domain or IP), the exploit must involve some error in destination selection, or simply allowing a mitm to impersonate microsoft.

this is inline with Attack Complexity High, attacker needs to be either in the network path (mitm) or control the erroneous destination of the connection (say mircosoft.com), possibly blocking (dosing) the higher priority genuine destination

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Seems odd even for a vibecoded copilot integration to make repeated, unprompted network requests. And if they're not repeated and unprompted, then we don't meet the "no user input" requirement.
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pretty standard to check for updates no?
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For others, def. For paint, it's always been either OS-updated or store-updated.
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Because the definition of "remote" has been expanded in the name of resume-driven development to include sending a malicious file that a victim has to open.
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