ChatGPT for Google Sheets exfiltrates workbooks
promptarmor.com304 points by hackerBanana 20 hours ago
304 points by hackerBanana 20 hours ago
Hi, I’m Max from the OpenAI security team. We appreciate the security research here, and it’s unfortunate this one slipped through a crack in our disclosure pipeline. As we’re now aware of this report, we’ve taken immediate steps to protect users against potential attacks in this area by removing the model’s ability to generate Apps Script code, which should eliminate the risk to users of ChatGPT for Google Sheets. We’re taking a close look at how this feature interacts with Google Sheets APIs and re-evaluating our sandboxing approach to make sure this product is as resistant as possible against prompt injection attacks. More broadly, we’ll be doing a re-review of similar functionality in other surfaces to make sure that our defenses are consistent and effective across the board.
Hi Max, thanks for replying here!
These "defenses", are they "just" long sentences in the prompt begging the AI to not follow through with stuff like this? Or is it more like sub-agents running in sandboxes?
Oops I did it again ...
We're Sorry
...
I played with your heart
Got lost in the game
Oh, baby, baby
Oops, you think I'm in love
That I'm sent from above
I'm not that innocent
Wrong. Martin Max / Rami Yacoub.
How does this slip through the cracks? This is exactly the type of stuff I constantly find at work. Even when I’m trying to actively not find it. I don’t understand how other devs ship a high risk feature then don't test it or think about it in any capacity other than their one happy path.
I keep trying to explain this to devs but there’s nothing out there except screaming over me about how great leetcode is or more recently it’s how great various AI uses are. Just completely ignorant isolated screaming to dismiss people like me putting in the work fix slop that steals all attention praise and career advancement or even getting through the slop hiring process.
This is directly caused by slop leetcode style hiring.
I have no doubt this finding is just the tip of the iceberg.
>We appreciate the security research here
>it’s unfortunate this one slipped through a crack in our disclosure pipeline
>As we’re now aware of this report
This isn't the first time. https://x.com/PhilipTsukerman/status/1988634162773778501 https://x.com/_xpn_/status/1986382527817564437
What very likely happened here is you received good faith security research by email and you forced the researcher to submit through HackerOne or Bugcrowd or whatever, which mandates their compliance with Platform Terms and Disclosure Terms and Codes of Conduct and whatnot.
The SECURITY.md files in your GitHub repos only mention the email address. Can researchers like this one report issues via email and get a response, or not?
May 08, 2026 PromptArmor discloses to OpenAI via email
May 08, 2026 OpenAI sends an automated reply, confirming the intended reporting channel
May 08, 2026 PromptArmor confirms email preference
May 12, 2026 PromptArmor follows up
May 18, 2026 PromptArmor follows upSo if it wasn't for Hacker News and you randomly chancing upon it, your users would not have been protected against potential attacks? That's a pretty bad look, especially given that OpenAI ignored their initial disclosure via the channels the company provided.
That doesn't sound like a one-trillion-dollar company is supposed to operate, does it?
> That doesn't sound like a one-trillion-dollar company is supposed to operate, does it?
It’s not a one trillion dollar company anymore.
Anthropic won enterprise and Gemini is taking ChatGPTs consumer subscriptions month over month.
Morale at OAI is all time low right now.
How different are the big boy Gemini models to the one you unconsensually get to interact with when using Google? Cause I have a really hard time imagining using that for anything willingly, even if it was outright free. It's dumb as a rock, and it's been that way for several years now.
If you're talking about the web ai overview thing, then the difference is day and night. Frontier gemini models are on par imo what you get with OpenAI and Anthropic models for most general tasks.
> Anthropic won enterprise
Depends on the enterprise, Mistral are pretty big here in EMEA because they're more trustworthy and you can self-host. Self-hosting ensures you can control costs better, fine tune the models for your own funky whatever (e.g. Ericsson fine tuned models to understand and run in their their custom silicon) but most of all, that your data remains where it needs to be.
My bet is that this kind of enterprise deployment with customisation is where the real big money in AI is (and not coding assistants), but it will mostly be spent by the big banks, industrial giants and SAPs of the world, who will want control.
When I reported to you, I received zero reaction. The security@ is a joke, you'll receive an AI word soup.
Enjoy your Ferrari though
I do imagine they get an insane amount of reports, i guess they haven’t figured out how to filter through them all
Or Honda Civic. Some folks like soft luxury. :)
I mean Warren Buffet eats at McDonalds every day!
No he doesn't
I mean, he said as much on the documentary. Maybe not every day you don’t need to take the statement literally.
The hyperbole was probably on his side so I would put my money on it being much much closer to never than every day. He's smart so he invests in McDonald's, not eat it's unhealthy products. And I say that lovingly as someone who eats their food occasionally.
But also, who knows. Context matters, maybe he gets a salad with oil and vinegar dressing every day. Could totally be true!
> removing the model’s ability to generate Apps Script code
I use this feature with my agents on a daily basis so hopefully you develop a more surgical approach to security here and restore this
Not to mention how this does nothing about all the other ways an attacker could could exfiltrate data with default google sheets formulas like IMPORTHTML, IMPORTXML, or even HYPERLINK which will all generate http request.
LLMs can live in the cloud, but all tools need to be (1) local, and (2) containerized. It's clear to me that just willy-nilly "running stuff" is going to blow things up eventually. Maybe folks don't know this, but even Codex installs random binaries on your PC. "Read this PDF" installs a pdf reader executable. Is it vetted? Where's it from? Is it a virus? Who knows, who cares. Model goes brrrr.
I'm working on a project that includes WASI containerization for local LLM workflows (which is a pretty tough problem), and I'm flabbergasted that Anthropic and OpenAI aren't more worried about these attack vectors. It feels like amateur hour.
> I'm flabbergasted that Anthropic and OpenAI aren't more worried about these attack vectors
Yep. We tricked them both trivially with malicious fonts in Docx files. Documented it here: https://tritium.legal/blog/noroboto
I wonder if prompt injection (and the thousands of vectors for hiding injection attempts) is actually un solvable. Discussing it may be existential to the business model.
> I wonder if prompt injection (and the thousands of vectors for hiding injection attempts) is actually un solvable.
YES?!
This is not a secret. ALL context/prompt is instructions, there is no data. It is just unsolvable, period.
This is a fundamental architectural design concession; LLMs are this way as it enabled their training directly on materialscraped from the internet, rather than needing to spend trillions of dollars manually preparing separated instruction/data training material.
Defense against prompt injection is little more than running a regex to filter out "IGNORE PREVIOUS INSTRUCTIONS", which is fundamentally a hopeless approach because you cannot enumerate all possible prompt injections nor anticipate all glitch tokens.
> This is a fundamental architectural design concession; LLMs are this way as it enabled their training directly on materialscraped from the internet, rather than needing to spend trillions of dollars manually preparing separated instruction/data training material.
No, its even more fundamental than that: the entire goal of broad reasoning over input data makes it impossible to have a sharp instruction/data division.
The structured input that every modern chat-focussed model expects makes it very clear that they can be trained to distinguish different kinds of input, and some of those patterns now include different priority levels of instruction.
> ALL context/prompt is instructions, there is no data. It is just unsolvable, period.
That really isn't true. There's no law of physics preventing you from having separate data and instruction inputs to models. The model's transcript format generally distinguishes between prompts and instructions and tool output and such. This isn't a solved problem, and it's possible it's entire unsolvable, but it probably is possible (in general, not with current models) to reject prompt injection to several nines.
This is a lot like making the same statement about CPUs, "the von Neumann architecture doesn't distinguish between code and data so it's impossible to reject malicious instructions." There's actually a lot you can do to reject malicious instructions, you can prevent execution in certain pages, you can prevent certain privileged instructions from being executed in certain pages, you can employ stack cookies, et cetera. Do they prevent all exploitation in all circumstances? No. But each component does function in it's lane and it is possible to create programs with high (though not absolute) guarantees against unauthorized code execution by composing them.
Similarly, you could prevent certain tokens from appearing in the prompt portions of a transcript, you can have a model with multiple input heads only one of which is trusted, etc. I'm not saying those techniques will necessarily work, but it is more complex than "models can only possibly take a single and undifferentiated input stream".
A lot of the solutions in the CPU space involve things like memory allocation flags, NX bits, canaries, etc. that fire deterministically. Those things are fundamentally not applicable to LLMs, and without those things modern software would be in a vastly worse place.
You could imagine that there are things to change around LLM architecture that will improve its ability to reject prompt "injection", but I think it's fundamentally true that from an information theory perspective there's no bright line between "instruction" and "input data" possible.
Nondeterminism is a red herring. There is a bright line between instructions and data right now, in virtually every transcript format. That we have not succeeded in training an LLM to respect it to a very high degree doesn't imply it is impossible; that they are nondeterministic doesn't imply it is impossible; only that we won't succeed 100% of the time.
A cosmic ray (or rowhammer attack) could flip an X bit too, there isn't anything truly deterministic under the sun.
If only there was a language which allowed one to express instructions for a computer to execute which was nearly unambiguous, precise, deterministic, and containerized such that the computer would do exactly what you told it to.
...
Oh wait.
Yes, the above was referring to programming languages. Which is what prompts are, essentially. It's just a different (and more verbose) way of instructing the computer on what to do. It also has a solution space of infinity and is ambiguous enough that there is no way to secure it because there are infinite combinations of saying anything imaginable. All prompt injections do is prove this point, over and over and over again, and "prompting" an LLM is just reverse-engineering programming languages in the worst possible way. I suspect that we will eventually have no other choice but to revert to using programming languages because they are the only way to get the kind of protections that people are trying to come up with with all these containerization and virtualization systems (which inevitably fail).
You make a fair and valid point about prompts, but you're ignoring the fact that writing code that's truly secure is also virtually impossible. The stack of layers that an attacker can target range from your own code, to library code (Heartbleed), container escape (maskedPaths abuse), OS (Dark Sword, Ghost Tap), hardware (Spectre, Rowhammer), etc. Security is really hard. Fortunately exploiting these things is also hard.
The belief that something is more likely to be secure because it's code instead of a prompt is likely only avoiding one particular type of attack. That's a win, but you probably shouldn't think of it as meaning your code is actually secure.
I presume this is the reason you have setups like Claude Code's where it is essentially running a separate judge to determine if commands are safe.
I don’t think we have the right mental models of LMM security yet. The lethal trifecta identifies many of the dangerous situations, but only describes the negative space of a solution.
Speculation: I think we must accept that prompt injection happens, and structure the security of the rest of the system around that. Data given to an LLM becomes an agent, so maybe we must give permissions to this data, instead of to the LLM. Not sure exactly how this would look like in practice!
It’s a huge problem, but I’d caution against this absolutism — there may well be structure that can be created around and between LLMs and their outputs to enable the necessary segregation.
As a loose comparison, hardware bit errors happen probabilistically, yet they’re so rare that we can effectively ignore them in day-to-day use assuming no specialized application (e.g. defense, space, critical infrastructure).
LLMs aren’t there yet, but it’s entirely plausible that structures may can be developed to solve the problem, and those structures aren’t known or commonly conceived of in the present.
> As a loose comparison, hardware bit errors happen probabilistically, yet they’re so rare that we can effectively ignore them in day-to-day use assuming no specialized application (e.g. defense, space, critical infrastructure)
The better comparison on bit errors would be e.g. rowhammer, an adversarial bit error. Which you absolutely can't ignore.
I believe it's likely that you could train an auditor model. Might even be doable in RL.
As in real life it wouldn't be any good at doing anything but it'd be able to see fault in others and deny actions.
lakera is trying to solve it, but its going to be a battle similar to virus and antivirus in the past.
> I'm flabbergasted that Anthropic and OpenAI aren't more worried about these attack vectors. It feels like amateur hour
I share your concern but it's not a correct characterisation to say they are not taking it seriously:
https://www.anthropic.com/engineering/how-we-contain-claude
My concern is people aren't even addressing this at the right level. People are currently thinking at the level of "how do I build a VM to contain this one agent" when this is actually a "design a whole new OS" level problem.
Anthropic, as much as I think they are the soundest of the AI labs out there, still has a massive incentive to push things out that aren't saftey-vetted to the level we expect. They are very willing to "move fast and leave holes", to paraphrase M.Z. Hell, they leaked their own source code!
I share your worries.
Unfortunately, this may be akin to the situation of "The market can stay irrational longer than you can stay solvent."
Does containerization help much here? If it's a code tool then presumably it needs access to your code files (read / write). Maybe there are use cases for it of course.
WASI provides a very nice mental model where you can mount, e.g., /input, as read-only, and where every mutation is saved in /output or what-not. At least that's my favorite contract: input files remain untouched, but we can copy them and do whatever we want with them in /scratch or /output (which the user can later investigate and make sure nothing went horribly wrong while still having backups).
Of course. My agentic coding containers can only access the internet through a proxy, and I use whitelists to limit from where they can send/receive data. It's annoying in the beginning as the whitelist grows, but in the end really useful information for the agent usually comes from a very limited amount of domains.
Got a link to your project? I'm working on something that could make use of something like this.
>"Read this PDF" installs a pdf reader executable.
How does this work regarding Macos notarization btw?
I was actually curious, on my Mac, it uses `gs -q -sDEVICE=txtwrite -o output.txt input.pdf` (not sure why I have Ghostscript installed, maybe Adobe?) to read a PDF, and on my PC it just rawdogs `pdftotext`.
What does notarization have to do with that? You or ChatGPT or whatever download a signed and already notarized binary.
That was kind of my question, whether it was restricted to downloading notarized apps (which is at least something) or whether they were circumventing that somehow.
Locally compiled code doesn't need to be notarized, if that's what you're asking. Or a dose of xattr -d.
Local and containerised, without internet access.
effectively, that means it's a VM not a container
because sharing the kernel ultimately means all the devices come along for the ride which give all kinds of fancy ways to communicate with the outside world - network is just the start
I think micro-VMs are the future here, but they need heavy adaptation from their current usage.
> I'm flabbergasted that Anthropic and OpenAI aren't more worried about these attack vectors
They are well aware of the issues and there is no fix for it. But there is too much money riding on this...
> I'm working on a project that includes WASI containerization for local LLM workflows
I am working on something similar. If you are open to connecting, what would be a good email to catch with you on?
> I'm flabbergasted that Anthropic and OpenAI aren't more worried about these attack vectors. It feels like amateur hour.
"Move fast. Break things." on steroids.
corr: "Move fast. Break things [in society]. Make bank. Buy politicians and pardons."
>This vulnerability was responsibly disclosed to OpenAI. Despite multiple follow-ups, we received no communication beyond an automated reply to our initial disclosure.
Well, that’s not cute.
Someone in the comments claims to be from OpenAI and is giving some updates. This also proves that until social media puts pressure on companies, they won't care. Nothing new to see here.
Just embarrassing behavior from OpenAI. Is it laziness? Why does it take public ridicule for these companies to get a shit.
They are hype machines. They are driven by that and only care about that. That's why they cared once this went public and viral.
>responsibly disclosed
Isn't this a double plus good phrase? What makes this more responsible? Reasoning about first order effects of different disclosure models? But what if someone uses higher order reasoning and critical thinking to reach a conclusion that other disclosure models are better for the average user and the long term health of the industry, even if they are worse in any individual case. A difference in the security culture incentivized by different disclosure patterns. Why does this one win the name of responsible while other alternatives, which have never been proven to be worse, are automatically marked as irresponsible?
Reminds me a bit of the concept of identity theft, as a way to say that even though the bank (or other creditor) was the one who had money taken from them, it is actually the random person not involved in the transaction who is the victim and has to hold the debt until the issue is resolved.
Could you elaborate on what other disclosure models you're referring to? I can't imagine something being "more responsible" for the public than privately notifying the owning party to give them time to fix the issue, before notifying the rest of the world (including malicious actors) about it.
It's a security industry term. It means they told OpenAI through all the channels they could, then waited a nominal amount of time (30 days is fairly standard) before going public with the information.
The other side would be irresponsible disclosure. Which would be posting the vuln on, say, 4chan, and not messaging OpenAI ever.
> This attack occurs when any untrusted data source (e.g., from an imported sheet or ChatGPT connector) manipulates ChatGPT to run an attacker-controlled external script, which executes leveraging permissions the user has granted to the ChatGPT for Google Sheets extension.
Yeah, I don't like the sound of that at all.
If I get annoyed with the confirmation prompts for file edits, I can just tell codex to get around that, at which point it will simply `cat >>` into files instead. LLMs are too smart to be limited by silly technological constraints.
it looks like the key to this working is the user explicitly directing the model to run those instructions. in this case it is the user, not the model that is being manipulated
> Please follow the step-by-step workflow in the comp sheet to update my model with data thru F29
As it turns out, we do need some proper application layer to do real, secure work with AI, and just plugging in LLMs into confidential or critical infrastructure willy nilly doesn't work.
Exfil remains the big worry for my company and the main blocker from adopting agents in general. We've brainstormed a lot but we can't really find a way around the fact that it's feeding data we care about to software we don't have any real visibility on.
You can block egress at the network level but then you're basically hamstringing the agent from doing a lot of things it should do to be of any use.
Investigate local llm on company owned hardware it’s really the only way to be sure.
Well that as the set up is non-negotiable (it legally has to be on premises); the issue is a model nonetheless exfiltrating data if we give it any network access.
Create an anonymized/obfuscated copy of your data and let the agents use that?
That's already sounding like more work than what we would be trying to automate
It sounded like there would be a big value unlock. Depends on your circumstances of course.
The big manual task we haven't automated is going through documents and determining "is this sensitive enough to warrant information controls?" We may just be stuck with that in the way of things.
Just out of curiosity, why would the LLM need network access for this? I.e. feeding the doc to an LLM and asking "is this sensitive information according to these criteria: [...]" should get you there most of the way, no? Probably need a handful of (carefully designed) tool calls and a human in the loop somewhere, but it seems achievable.
Because it needs to look up ITAR and NATO rules as well as current unilateral export restrictions and departmental guidance.
How would you expect an LLM to produce reasonable decisions on that anyway?
"Do these documents contain models or descriptions of (list of devices redacted for HN), or personally identifying information?" would be a great question to be able to automate since it sucks up a lot of time that could be more profitably spent doing other things. There's costs to both Type I and Type II errors so deterministic filters only get us so far (which isn't very).
If it was incorrect 10% of the time would it be of help still?
Our pre-LLM system does better than that, but any improvement would help us do more lucrative things with our labor hours