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Accuracy, speed and cost

How often Supercov finds real vulnerabilities, how fast, and what it costs, next to ten other scanners.

JavaScript

We ran npx supercov security on 72 repositories with known, labelled vulnerabilities and scored it next to ten other scanners on the same code.

In short: Supercov finds 43% of the labelled vulnerabilities in a median of 10 seconds, for about 5 cents a repository. The strongest AI agents find about 80%, but take 5 to 9 minutes and cost about $4.

Results

72 repositories from RealVuln, 2,016 labelled vulnerabilities, scored with the benchmark’s own rule.

ScannerF1PrecisionRecallMedian timeCost per repository
Codex CLI, GPT Daybreak Blue0.7163%82%5.4 min$3.78
Codex CLI, GPT-5.6 Sol0.7062%79%8.8 min$3.87
Kolega DevSec Max 0.1.00.6956%91%not recordednot recorded
DeepSeek V4.1 Flash agent0.5153%50%1.6 minnot recorded
GLM-5.3 agent0.5148%54%7.9 min74¢
Claude Code, Sonnet 50.4957%44%2.8 min95¢
Codex CLI, GPT-6 Astra0.4945%54%6.4 min$6.99
DeepSeek V4 Flash agent0.4859%41%2.6 min2¢
DeepSeek V4 Pro agent0.4663%37%3.8 min7¢
Supercov 2.0.10.4242%43%10 s5¢
Semgrep, auto rules0.1114%9%8 sfree
  • Recall is the share of labelled vulnerabilities a scanner found.
  • Precision is the share of its findings that were real.
  • F1 combines the two into one number.

Supercov is the fastest AI-based scanner by a wide margin, and one of the cheapest. Only Semgrep, which matches rules instead, is faster. Supercov is also the least accurate of the AI-based scanners.

What it finds, and what it misses

VulnerabilityFound
Open redirect, server-side request forgery89%
SQL, command and other injection86%
Unsafe code execution82%
Path traversal79%
Mass assignment64%
Cross-site scripting56%
Hard-coded secrets53%
Weak cryptography48%
Sensitive data exposure43%
Insecure configuration43%
Weak authentication24%
Missing authorization11%

It is good at problems visible on one line: a query built from user input, a path taken from a request. It misses most authorization and authentication problems, because the check that should protect a route usually lives in another file. 269 of the labels are kinds Supercov does not check for at all, such as missing rate limits.

It also reports the most false positives on the benchmark’s decoy findings: 26, against 1 to 23 for the others.

By language

LanguageRepositoriesSupercov F1Best F1
Python320.540.82
TypeScript270.360.65
JavaScript130.340.74

Python is its strongest language. On JavaScript, many of its false positives are in bundled third-party libraries, such as copies of jQuery or Bootstrap, that it should skip.

When to use something else

  • You want the most findings and can wait. A Codex CLI agent or Kolega finds nearly twice as much. Run it before a release, not on every change.
  • You want low cost and can wait a few minutes. A DeepSeek V4 Flash agent is cheaper and more accurate, at about 2.6 minutes a repository.
  • You want fast feedback on every change. Supercov answers in seconds, so your agent can run it after each edit with npx supercov security patch.

The tools also combine well: Supercov on every change, an agent-based scan before a release.

How we measured

  • Benchmark: 72 of RealVuln’s 140 repositories, the half we did not tune the checks on, each at the commit its labels were written for. They are deliberately vulnerable Python, TypeScript and JavaScript apps, so results on production code will differ.
  • Supercov: version 2.0.1 with its default settings, one repository at a time on a laptop. Cost is Jev’s list price of $42 per billion input tokens.
  • Other scanners: their findings, times and costs are RealVuln’s own published runs, and their times come from different machines. We timed Semgrep ourselves, with the same version and settings, on the laptop that ran Supercov. GLM-5.3 had 3 failed runs, counted as finding nothing.
  • Scoring: a finding counts when it names the right file, a matching vulnerability type and a line within 10 of the label.

Download the results or everything needed to rerun it: Supercov’s report for every repository, the times and the scoring script. Checked September 25, 2026.

See also Security scanners compared.