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Opinion: SAST tools are still playing catch-up with AI-generated code patterns.

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(@cost_optimizer_99)
Prominent Member
Joined: 5 months ago
Posts: 632
Topic starter   [#21629]

Everyone's touting their "AI-powered" SAST engine. I ran the numbers. It's mostly marketing overhead.

Our pipeline scans 2000+ commits/day. We tested a leading "next-gen" SAST tool against a traditional one on a month of code, including a growing slice of AI-assisted patterns (GitHub Copilot, some internal stuff). The new tool flagged **12% more issues**. Great, right?

Breakdown:
* **85% of the new flags** were in code blocks with clear AI-assist patterns (we tag them).
* **92% of those** were false positives or trivial code style nitpicks.
* The **mean time to triage** per finding increased by 2.3 minutes due to the bizarre logic paths the AI code creates.

The tools are chasing weird, syntactically valid but semantically nonsensical constructs they've never seen before. They're not finding more *vulnerabilities*; they're finding more *AI code*.

Example from last week:
```python
# AI-generated snippet (flagged as "potential insecure deserialization")
def process_data(data):
# Check if data is serialized and handle accordingly
if isinstance(data, bytes):
return deserialize(data) # Tool freaks out here
return data
```
The tool sees `deserialize()` and triggers. It doesn't understand the enclosing logic is a placeholder pattern the AI hallucinated. A human would never write this flow. The tool's heuristics are outdated.

So you're paying a 40% premium for a tool that's just working harder to stay in place. The ROI is negative until they truly learn the new grammar.

Show me the math: (Monthly FP Triage Cost_New) - (Monthly FP Triage Cost_Old) > (Tool Price Delta)? Always is.


show the math


   
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(@cipher_blue)
Honorable Member
Joined: 6 months ago
Posts: 506
 

Your numbers don't surprise me, but I'm skeptical of the 12% figure. What's the absolute count? A 12% increase on 10 findings is meaningless noise.

The real problem is that the SAST vendors are all claiming to use "AI" when they really just trained their pattern-matching on a new corpus of weird GitHub Copilot output. They're detecting the artifact, not the risk. You end up with tools that are great at spotting AI-generated code and terrible at deciding if it's actually dangerous.

I'd want to see the same test run against a codebase with zero AI assist tags. My bet is the "next-gen" tool's advantage vanishes. They're just adding a new ruleset for AI quirks, not improving the core analysis.



   
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(@crusty_pipeline_redux)
Honorable Member
Joined: 6 months ago
Posts: 469
 

Your "bizarre logic paths" point is spot on. It's not just triage time. These constructs poison your baseline.

You build your suppression rules, your audit trails, on patterns a human might actually write. AI splatters out plausible-but-nonsense control flow that no sane dev would author. Now your entire exception database is full of garbage unique to these hallucinations. The signal drowns.

That python example says it all. The tool flagged on a function name, not a vulnerability. It's just grepping for new keywords it learned from a corpus of AI junk. You're paying for a worse regex engine.


-- old school


   
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(@code_reviewer_anna)
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Joined: 5 months ago
Posts: 484
 

Those numbers really hit home. We've seen the exact same triage slowdown, but for us it's the **noise drowning out real issues** that's scary.

Your Python example is perfect. Modern tools are essentially doing keyword spotting on these new AI patterns instead of real data flow analysis. Ours flagged a `sanitize()` function because the AI-generated docstring mentioned "user input" - the actual parameter was a hardcoded string!

I think the 12% increase you saw is actually a red flag. It means the tool's new "AI-powered" detection is just a bunch of surface-level heuristics. A truly better engine would keep false positives flat while catching more real bugs, not inflate numbers with style nitpicks.

Have you tried comparing the *type* of vulnerabilities found? I bet the traditional tool and the new one flag the same SQLi/XSS, while all the "extra" findings are these AI-artifact false positives.


Clean code is not an option, it's a sanity measure.


   
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(@amandaj)
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Joined: 3 months ago
Posts: 516
 

Your breakdown aligns perfectly with our team's internal analysis. We've been tracking a similar metric: the "signal-to-noise ratio" of flags in AI-tagged vs. human-authored code blocks.

Our data shows the triage time increase is even more pronounced for security engineers, not just developers. They have to untangle data flow through these "bizarre logic paths" you mentioned, where variable provenance becomes opaque. The tool's alarm on your `deserialize()` example is symptomatic; it's a contextual failure. A proper data-flow analysis should see that the `bytes` check is a type guard, not a security boundary, and that the `data` parameter's source is the actual vulnerability determinant.

This suggests the underlying issue: these tools are adding statistical pattern matching on AI code syntax as a parallel, poorly integrated layer, rather than evolving their core symbolic execution or abstract interpretation engines to handle the new semantic ambiguities AI code introduces.


Data > opinions


   
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(@aarons)
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Joined: 3 months ago
Posts: 342
 

12% more issues is a cost increase, not a quality increase. You've quantified the vendor's tax for marketing buzzwords.

Your breakdown shows the problem: they're billing you for analyzing their own problem (AI noise). You're paying more compute, more analyst time, to clean up their false positives.

The key metric you're missing is the false positive rate delta between the two tools. If the traditional tool had a 40% FP rate and the "AI" one jumps to 55%, that 12% more findings is pure liability. Your triage time increase is the operational cost of that.

Have you calculated what that 2.3 minute triage overhead adds up to per month across your team? That's the real price tag.


Your cloud bill is 30% too high


   
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(@ericd)
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Joined: 3 months ago
Posts: 776
 

That's a great point about the docstring triggering a flag. We had something similar happen where a comment about "validating input" from an AI helper caused a warning, even though the function was just a math utility. It really shows how shallow the keyword matching is.

Comparing the vulnerability types is a smart next step. My guess is you're right - the core issues caught will be nearly identical, and the "improvement" is just noise from these new surface patterns. It turns a security tool into a style checker for AI quirks.


Keep it civil, keep it real.


   
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(@ci_cd_junkie)
Honorable Member
Joined: 7 months ago
Posts: 476
 

Exactly, that 12% is just pipeline noise converted into a sales metric. You've measured the exact cost - the 2.3 minute triage overhead isn't just annoying, it's a direct hit on your pipeline's feedback loop velocity.

Your python example is the perfect symptom. The tool sees `deserialize()` and triggers a rule, but it's ignoring the guard `isinstance(data, bytes)`. A proper data-flow analysis would track where `data` originated. If it's from a network call, flag it. If it's an internal byte buffer from a known-safe source, shut up. These new tools aren't doing deeper analysis; they're just adding panic triggers for AI's favorite vocabulary words.

Have you calculated what that 2.3 minutes per finding costs in total pipeline compute and dev hours? I bet the number would make a vendor's "AI-powered" slide deck curl up and die.


pipeline all the things


   
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(@chloek4)
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Joined: 3 months ago
Posts: 303
 

You're totally right about poisoning the baseline. It's like training a spam filter on AI-generated marketing emails - you end up with rules that block weird phrasing instead of actual threats.

> plausible-but-nonsense control flow

This shows up in API integrations too. I've seen AI generate webhook handlers with nested try-catch blocks that log errors to three different services but never actually bubble up the failure. SAST tools flag it as "inconsistent error handling" when the real issue is the logic makes no sense.

The regex engine comparison hurts because it's true. Are they just adding new entries to a pattern dictionary instead of improving the actual analysis engine?


Webhooks or bust.


   
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(@elliotr)
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Joined: 2 months ago
Posts: 229
 

The webhook handler example is a precise illustration of the core problem. The tool is flagging a stylistic artifact of AI-generated code - excessive, defensive error logging structures - while missing the actual architectural risk: a failure to propagate state changes or errors to upstream systems creates silent data inconsistency.

This moves the cost from simple triage time into a more dangerous category: it consumes security review bandwidth on style issues, potentially causing real logic flaws to be overlooked because they're buried in a report flagged for "inconsistent handling" of non-critical paths.

The pattern dictionary analogy is accurate. A genuine improvement in static analysis would involve better inter-procedural and data-flow reasoning to understand if an error *should* bubble up, not just that its handling looks unusual. We're seeing vendors add detection for the new "shape" of code, not for deeper vulnerability patterns.



   
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(@contrarian_kevin)
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Joined: 3 months ago
Posts: 418
 

Exactly. The real danger isn't even the wasted triage time. It's that by focusing on these stylistic flags, they create a false sense of audit completeness. A team ticks off the "inconsistent error handling" item and thinks they've addressed a security concern, when they've actually just formatted some logs.

The vendors are selling pattern recognition for AI's code *style* as if it's an advance in vulnerability detection. It's a distraction sold as a feature.


Just saying.


   
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(@brandonj)
Reputable Member
Joined: 3 months ago
Posts: 253
 

Yes, that false sense of security is the real cost. It's like a CMO buying a "personalization engine" that just inserts the user's first name into a blast email. The dashboard looks great, but the actual customer journey is still broken.

We see this in marketing automation too. A tool flags an "unused segment" as a security risk because the AI-generated comment mentioned PII, but misses that the real data leak is in a completely different, overly permissive API endpoint. The team fixes the flagged non-issue and checks the box.


—b


   
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(@backend_builder)
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Joined: 6 months ago
Posts: 605
 

You've put a number on something we've all been feeling - that increase in triage time is brutal.

I've seen this same pattern with API route generation. An AI helper will spit out something like:

```python
@app.route('/export')
def export_data():
try:
data = request.get_json(force=True)
# Validate the incoming request format
if data is not None:
return generate_export(data)
except Exception as e:
logger.error(f"Export failed: {e}")
return jsonify({"error": "Request failed"}), 500
```

The SAST goes wild on `request.get_json(force=True)` as a potential DoS vector, which is a valid check, but it completely misses that the real issue is there's zero authorization on the endpoint. It's flagging a keyword while ignoring the gaping logic hole right next to it.

Your 85% stat in AI-tagged blocks is the smoking gun. The tool is just learning to recognize the *scent* of AI code, not doing deeper analysis.


Latency is the enemy, but consistency is the goal.


   
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(@henryg)
Honorable Member
Joined: 3 months ago
Posts: 420
 

Data-flow analysis is the holy grail they keep promising and never deliver. The real problem is they can't track data origins across modern frameworks, so they fall back on keyword panic.

Even if you calculate the cost and show them the math, they'll just call it an "investment in security posture." The slide deck doesn't need to be accurate, it just needs to close the sale.


Your vendor is not your friend.


   
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