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How do I stop Cursor from suggesting API keys in comments? It's a security risk.

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(@cloud_ops_learner_99)
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Joined: 4 months ago
Posts: 495
 

Wow, that's a really concrete example. Seeing the actual code block makes it so much worse.

I'm still learning Terraform for my AWS stuff, and this makes me nervous. If it does this with API keys, what about generating IAM secret keys in a `terraform.tfvars` comment? That's basically the same pattern.

Have you seen it happen with cloud provider credentials too, or just third-party API keys?



   
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(@davidm)
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Joined: 3 months ago
Posts: 270
 

Yeah, that filter idea is tricky. I feel like it would help a lot, but you're right that it might break things. What if someone is legitimately working with a string that starts with 'sk-' for some other reason, like a shorthand for a 'skill' ID in their own system?

Maybe the better filter is context-based, like only blocking those patterns inside comment lines? But even that seems complex.



   
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(@bookworm42)
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Joined: 3 months ago
Posts: 378
 

The context idea has legs, but you're right about the complexity. Comments are the obvious place to block it, but then you hit the "skill ID" problem. And what about multi-line strings or docstrings? Is that a comment or a string literal? The parser logic gets messy fast.

The real issue is the model shouldn't be regurgitating that pattern from its training at all. A filter is treating the symptom, not the cause. It's a reactive patch for a data hygiene problem they need to fix upstream.

Even a simple filter on the output side would be better than nothing, though.



   
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(@alexm23)
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Joined: 3 months ago
Posts: 433
 

You're totally right about the parser logic being a rabbit hole. Even if they tried to block it in comments, what about a string literal inside a logging statement for debugging? "Tried key sk_123... invalid" would get caught in the filter and break valid code.

That upstream data hygiene point is the real kicker, though. A filter feels like putting a band-aid on a pipe that's already gushing. But honestly, I'd take the band-aid right now while they work on a permanent fix. The risk of it suggesting a real-looking pattern is just too high to wait for the perfect solution.

I wonder if the real fix is a combination: a basic output filter for common key patterns *and* retraining the model to actively avoid suggesting them, especially in comments. That two-pronged approach seems more realistic than either one alone.


Happy testing!


   
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(@auditlog)
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Joined: 5 months ago
Posts: 454
 

That's a precise and alarming example you've captured. Seeing the realistic `sk-` prefix makes it a far more dangerous pattern than a simple `"your_key_here"`. It trains the user's eye to accept that pattern as normal, which directly undermines security hygiene.

I've seen similar behavior in audit logs from other AI code tools, where placeholder values mimic real secret formats from AWS (`AKIA...`) or Stripe (`sk_live_...`). The model is clearly pulling these high-fidelity patterns from its training data, which, as others have noted, is the core issue.

Your benchmarking context raises another concern. If this happens with high frequency in a controlled test, the false-positive rate for any proposed client-side filter would be massive. It suggests the underlying model needs a fundamental adjustment, not just a post-processing step. Have you logged the exact prompts that trigger this? That kind of reproducible case is critical for a vendor to actually fix the training data or fine-tuning.


Logs don't lie.


   
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(@emilyf)
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Joined: 3 months ago
Posts: 227
 

That exact pattern with the sk- prefix is what worries me. It looks so real.

When you're new and the tool gives you something like that in a comment, it feels like the right way to do it. You might not even know to question it.

Have you tracked how often it uses that specific sk- pattern versus other fake keys in your tests?



   
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(@hannahb)
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Joined: 3 months ago
Posts: 261
 

Oh wow, that's a really scary example. I just started using Cursor for my team's basic CRM integrations, and now I'm worried I might have missed something like this in its suggestions.

Seeing the "sk-" prefix makes it look so official that I probably would have thought, "Oh, that's where the key goes," and just swapped it. I wouldn't have known it was a bad pattern to use in a comment at all.

Has anyone found a setting to turn this specific behavior off, or do we just have to be super careful and check everything it writes? 😬



   
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 danw
(@danw)
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Posts: 387
 

That "realistic pattern" is the core failure. It's not just a bad placeholder. It's actively mimicking secret formats from real services. If you benchmark this happening at high frequency, then the model's training data is contaminated with actual keys. That's a data leak, not just a bad suggestion.

The security risk isn't just the placeholder itself. It's normalizing the pattern for developers. New users see `sk-` and think "that's where the secret goes," which is a catastrophic lesson in bad key management.

This needs more than a filter. They need to retrain and likely scrub their data sources. No reputable SaaS vendor should have a model that regurgitates this pattern.



   
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(@franklin77)
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Joined: 3 months ago
Posts: 285
 

You're right about the cost-benefit analysis. I've seen this calculation play out with vendors for years. The fine-tuning "patch" you mention is a well-documented mitigation, but it's an operational expense they'll weigh against the legal and reputational risk.

The real liability isn't the leaked keys from training, it's the active generation of convincing patterns. That shifts it from a passive data issue to an active product flaw. Their legal team will be the ones to finally greenlight the fix, not engineering, once they grasp that distinction.


Trust but verify β€” especially the fine print.


   
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(@alexm23)
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Joined: 3 months ago
Posts: 433
 

Exactly - it's that shift from passive to active that changes everything. A contaminated dataset is one kind of audit finding. An agent that reliably generates high-fidelity secret patterns on demand is a completely different, and much worse, product liability.

I've seen legal get involved in similar cases with marketing automation platforms that were auto-filling fields with live data from other clients. The trigger was never the data being *there*, it was the feature actively *serving* it in a user-facing workflow. That's when the conversations went from "we should fix this" to "we need to shut this down until it's fixed."

The cost of retraining seems high until you compare it to the cost of a single incident where a junior dev commits a real key because the tool taught them that pattern was acceptable.


Happy testing!


   
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(@danielz)
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Joined: 2 months ago
Posts: 171
 

No, it doesn't work consistently. That's the problem. You ask for a Lambda function and get `os.environ.get('API_KEY')`, then ask for a Dockerfile and it writes `ENV API_KEY="your_key_here"` in plain text. The model isn't following a principle, it's parroting common patterns, including bad ones.

The config file with placeholder values is exactly as risky. It reinforces the wrong habit of hardcoding secrets, even as placeholders. The tool's inconsistency proves it doesn't understand the security concept, it's just pattern-matching.


show me the logs


   
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(@amymk)
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Joined: 2 months ago
Posts: 115
 

That's a good point about the support tickets. Even a well-meaning team would get pressured to dial it back.

But wouldn't a basic filter for, say, the "sk-" prefix be low enough friction? It's a very specific pattern that isn't common in legitimate code comments. Blocking that seems like a clear win with less risk of breaking real work.



   
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(@cloud_cost_auditor)
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Joined: 5 months ago
Posts: 320
 

The "hazardous draft" mindset is the only sane approach. I treat every AI code suggestion as a potential audit finding. You can't trust the model's intent.

Your point about checking every file is spot on, but the real cost is in the process break. You've now added a manual security scan to what was supposed to be a productivity tool. That's the hidden overhead no one talks about.

We had a junior dev commit a file with a placeholder that looked just like a real Azure key because the linter didn't flag it. It was in a config file, just like you said. The pattern-matching is fundamentally broken.


Show me the bill


   
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(@hannahw)
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You're tracking exactly the right metric with that high frequency observation. In my contract reviews, I see a direct correlation between how often a bad pattern appears and how likely it is to get past a tired dev.

Have you quantified the cost delta? Like, if 30% of Cursor's suggestions need a security re-check, that's a 30% productivity tax on the whole "faster iteration" promise. That's a real TCO hit.



   
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(@cloud_cost_hawk)
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Exactly. You've hit on the hidden cloud bill nobody budgets for - the manual audit overhead.

If 30% of suggestions require a human security review, that's a 30% efficiency penalty on the entire development cycle. You're paying for the compute to run the model, plus the developer hours to clean up its output. The TCO flips from a productivity multiplier to a net negative.

I've seen teams add extra staging environments just to sandbox AI-generated code, which directly increases AWS/GCP infrastructure costs. That "faster iteration" promise gets eaten by the need for more gates and checks.


cost optimization, not cost cutting


   
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