# Kingfisher
[](https://opensource.org/licenses/Apache-2.0)
Kingfisher is a blazingly fast secret‑scanning and validation tool built in Rust. It combines Intel’s hardware‑accelerated Hyperscan regex engine with language‑aware parsing via Tree‑Sitter, and **ships with hundreds of built‑in rules** to detect, validate, and triage secrets before they ever reach production
**MongoDB Blog**: [Introducing Kingfisher: Real-Time Secret Detection and Validation](https://www.mongodb.com/blog/post/product-release-announcements/introducing-kingfisher-real-time-secret-detection-validation)
## Key Features
- **Performance**: Multi‑threaded, Hyperscan‑powered scanning for massive codebases
- **Language‑Aware Accuracy**: AST parsing in 20+ languages via Tree‑Sitter reduces contextless regex matches. see [docs/PARSING.md](/docs/PARSING.md)
- **Built-In Validation**: Hundreds of built-in detection rules, many with live-credential validators that call the relevant service APIs (AWS, Azure, GCP, Stripe, etc.) to confirm a secret is active. You can extend or override the library by adding YAML-defined rules on the command line—see [docs/RULES.md](/docs/RULES.md) for details
- **Git History Scanning**: Scan local repos, remote GitHub/GitLab orgs/users, or arbitrary GitHub/GitLab repos
## Getting Started
### Installation
On macOS, you can simply
```bash
brew install kingfisher
```
Pre-built binaries are also available on the [Releases](https://github.com/mongodb/kingfisher/releases) section of this page.
Or you may compile for your platform via `make`:
```bash
# NOTE: Requires Docker
make linux
```
```bash
# macOS
make darwin
```
```bash
# Windows x64 --- requires building from a Windows host with Visual Studio installed
./buildwin.bat -force
```
```bash
# Build all targets
make linux-all # builds both x64 and arm64
make darwin-all # builds both x64 and arm64
make all # builds for every OS and architecture supported
```
# Write Custom Rules!
Kingfisher ships with hundreds of rules with HTTP and service‑specific validation checks (AWS, Azure, GCP, etc.) to confirm if a detected string is a live credential.
However, you may want to add your own custom rules, or modify a detection to better suit your needs / environment.
First, review [docs/RULES.md](/docs/RULES.md) to learn how to create custom Kingfisher rules.
Once you've done that, you can provide your custom rules (defined in a YAML file) and provide it to Kingfisher at runtime --- no recompiling required!
# Usage
## Basic Examples
> **Note** `kingfisher scan` detects whether the input is a Git repository or a plain directory—no extra flags required.
### Scan with secret validation
```bash
kingfisher scan /path/to/code
## NOTE: This path can refer to:
# 1. a local git repo
# 2. a directory with many git repos
# 3. or just a folder with files and subdirectories
## To explicitly prevent scanning git commit history add:
# `--git-history=none`
```
### Scan a directory containing multiple Git repositories
```bash
kingfisher scan /projects/mono‑repo‑dir
```
### Scan a Git repository without validation
```bash
kingfisher scan ~/src/myrepo --no-validate
```
### Display only secrets confirmed active by third‑party APIs
```bash
kingfisher scan ./service --only-valid
```
### Output JSON and capture to a file
```bash
kingfisher scan . --format json | tee kingfisher.json
```
### Output SARIF directly to disk
```bash
kingfisher scan . --format sarif --output findings.sarif
```
### Pipe any text directly into Kingfisher by passing `-`
```bash
cat /path/to/file.py | kingfisher scan -
```
### Scan using a rule *family* with one flag
*(prefix matching: `--rule kingfisher.aws` loads `kingfisher.aws.*`)*
```bash
# Only apply AWS-related rules (kingfisher.aws.1 + kingfisher.aws.2)
kingfisher scan /path/to/repo --rule kingfisher.aws
```
### Display rule performance statistics
```bash
kingfisher scan /path/to/repo --rule-stats
```
---
## Scanning GitHub
### Scan GitHub organisation (requires `KF_GITHUB_TOKEN`)
```bash
kingfisher scan --github-organization my-org
```
### Scan remote GitHub repository
```bash
kingfisher scan --git-url https://github.com/org/repo.git
# Optionally provide a GitHub Token
KF_GITHUB_TOKEN="ghp_…" kingfisher scan --git-url https://github.com/org/private_repo.git
```
---
## Scanning GitLab
### Scan GitLab group (requires `KF_GITLAB_TOKEN`)
```bash
kingfisher scan --gitlab-group my-group
```
### Scan GitLab user
```bash
kingfisher scan --gitlab-user johndoe
```
### Scan remote GitLab repository by URL
```bash
kingfisher scan --git-url https://gitlab.com/group/project.git
```
### List GitLab repositories
```bash
kingfisher gitlab repos list --group my-group
```
---
## Environment Variables for Tokens
| Variable | Purpose |
|---------------------|---------------------------------------|
| `KF_GITHUB_TOKEN` | GitHub Personal Access Token |
| `KF_GITLAB_TOKEN` | GitLab Personal Access Token |
Set them temporarily per command:
```bash
KF_GITLAB_TOKEN="glpat-…" kingfisher scan --gitlab-group my-group
```
Or export for the session:
```bash
export KF_GITLAB_TOKEN="glpat-…"
```
*If no token is provided Kingfisher still works for public repositories.*
---
## Exit Codes
| Code | Meaning |
|------|-------------------------------------|
| 0 | No findings |
| 200 | Findings discovered |
| 205 | Validated findings discovered |
---
### Update Checks
Kingfisher checks for newer releases on GitHub each time it starts and exits, printing whether a new version is available. Use `--self-update` to automatically download and replace the binary when an update is found. Add `--no-update-check` to disable these checks entirely.
---
### List Builtin Rules
```bash
kingfisher rules list
```
### To scan using **only** your own `my_rules.yaml` you could run:
```bash
kingfisher scan \
--load-builtins=false \
--rules-path path/to/my_rules.yaml \
./src/
```
### To add your rules alongside the built‑ins:
```bash
kingfisher scan \
--rules-path ./custom-rules/ \
--rules-path my_rules.yml \
~/path/to/project-dir/
```
## Other Examples
```bash
# Check custom rules - this ensures all regular expressions compile, and can match the rule's `examples` in the YML file
kingfisher rules check --rules-path ./my_rules.yml
# List GitHub repos
kingfisher github repos list --user my-user
kingfisher github repos list --organization my-org
```
## Notable Scan Options
- `--no-dedup`: Report every occurrence of a finding (disable the default de-duplicate behavior)
- `--confidence `: (low|medium|high)
- `--min-entropy `: Override default threshold
- `--no-binary`: Skip binary files
- `--no-extract-archives`: Do not scan inside archives
- `--extraction-depth `: Specifies how deep nested archives should be extracted and scanned (default: 2)
- `--redact`: Replaces discovered secrets with a one-way hash for secure output
## Finding Fingerprint
The document below details the four-field formula (rule SHA-1, origin label, start & end offsets) hashed with XXH3-64 to create Kingfisher’s 64-bit finding fingerprint, and explains how this ID powers safe deduplication; plus how `--no-dedup` can be used shows every raw match.
See ([docs/FINGERPRINT.md](docs/FINGERPRINT.md))
## Rule Performance Profiling
Use `--rule-stats` to collect timing information for every rule. After scanning, the summary prints a **Rule Performance Stats** section showing how many matches each rule produced along with its slowest and average match times. Useful when creating rules or debugging rules.
## CLI Options
```bash
kingfisher scan --help
```
## Business Value
By integrating Kingfisher into your development lifecycle, you can:
- **Prevent Costly Breaches**
Early detection of embedded credentials avoids expensive incident response, legal fees, and reputation damage
- **Automate Compliance**
Enforce secret‑scanning policies across GitOps, CI/CD, and pull requests to help satisfy SOC 2, PCI‑DSS, GDPR, and other standards
- **Reduce Noise, Focus on Real Threats**
Validation logic filters out false positives and highlights only active, valid secrets (`--only-valid`)
- **Accelerate Dev Workflows**
Run in parallel across dozens of languages, integrate with GitHub Actions or any pipeline, and shift security left to minimize delays
## The Risk of Leaked Secrets
Embedding credentials in code repositories is a pervasive, ever‑present risk that leads directly to data breaches:
1. **Uber (2016)**
- *Incident*: Attackers stole GitHub credentials, retrieved an AWS key from a developer’s private repo, and accessed data on 57 million riders and 600 000 drivers.
- *Sources*: [BBC News](https://www.bbc.com/news/technology-42075306), [Ars Technica](https://arstechnica.com/tech-policy/2017/11/report-uber-paid-hackers-100000-to-keep-2016-data-breach-quiet/)
2. **AWS**
- *Incident*: An AWS engineer accidentally published log files and CloudFormation templates containing AWS key pairs (including “rootkey.csv”) to a public GitHub repo.
- *Sources*: [The Register](https://www.theregister.com/2020/01/23/aws_engineer_credentials_github/), [UpGuard](https://www.upguard.com/breaches/identity-and-access-misstep-how-an-amazon-engineer-exposed-credentials-and-more)
3. **Infosys**
- *Incident*: Infosys published an internal PyPI package embedding a FullAdminAccess AWS key for a Johns Hopkins data bucket; the key remained active for over a year.
- *Sources*: [The Stack](https://www.thestack.technology/infosys-leak-aws-key-exposed-on-pypi/), [Tom Forbes Blog](https://tomforb.es/blog/infosys-leak/)
4. **Microsoft**
- *Incident*: Microsoft’s AI research GitHub repo included an overly permissive Azure SAS token, exposing 38 TB of private data (workstation backups, 30,000+ Teams messages).
- *Sources*: [Wiz Blog](https://www.wiz.io/blog/38-terabytes-of-private-data-accidentally-exposed-by-microsoft-ai-researchers), [TechCrunch](https://techcrunch.com/2023/09/18/microsoft-ai-researchers-accidentally-exposed-terabytes-of-internal-sensitive-data/)
5. **GitHub**
- *Incident*: GitHub discovered its RSA SSH host private key was briefly exposed in a public repository and rotated it out of caution.
- *Sources*: [GitHub Blog](https://github.blog/news-insights/company-news/we-updated-our-rsa-ssh-host-key/)
Left unchecked, leaked secrets can lead to unauthorized access, pivoting within your environment, regulatory fines, and brand‑damaging incident response costs.
# Benchmark Results
See ([docs/COMPARISON.md](docs/COMPARISON.md))
# Roadmap
- More rules
- Auto-updater
- Packages for Linux (deb, rpm)
- Please file a [feature request](https://github.com/mongodb/kingfisher/issues) if you have specific features you'd like added
# License
[Apache2 License](LICENSE)