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gosec-go

Configures and runs gosec - Go-specific SAST covering 40+ rule IDs (G101 hardcoded creds, G104 unhandled errors, G304 file path traversal, G401 weak crypto algorithms, G601 implicit memory aliasing, etc.); supports `gosec ./...` recursive scan via Go AST + SSA analysis with taint tracking; per-line `#nosec G404 -- justification` suppression; output formats `--fmt sarif|json|junit-xml|html|text`; integrates with golangci-lint as a linter. Use when the user works with Go and needs a focused SAST integrated with golangci-lint.

gosec-go

Overview

Per github.com/securego/gosec:

gosec is the Go-specific SAST. It "performs static code analysis by scanning the Go AST and SSA code representation" and supports "taint analysis tracking data flow from user inputs to dangerous functions" per gs-gh.

The taint analysis distinguishes gosec from regex-based linters - it tracks input flow through method chains, which catches injection patterns linters miss.

When to use

  • Repo has Go source (gosec is Go-only).
  • The team needs Go-focused SAST integrated with golangci-lint.
  • A CI workflow needs PR-blocking security gates for Go services.
  • Layered with semgrep-rules for cross-language coverage.

Step 1 - Install

Per gs-gh:

go install github.com/securego/gosec/v2/cmd/gosec@latest

For pinned versions in CI:

go install github.com/securego/gosec/v2/cmd/gosec@v2.20.0

Docker:

docker pull securego/gosec
docker run --rm -v "$PWD:/code" securego/gosec ./code/...

Step 2 - Basic recursive scan

Per gs-gh:

gosec ./...

Common variations:

gosec -severity=high ./...           # only HIGH severity
gosec -confidence=high ./...         # only HIGH confidence
gosec -exclude=G104 ./...            # skip "unhandled errors" rule
gosec -include=G101,G102 ./...       # only run specific rules

Step 3 - Rule ID catalog

Per gs-gh the common rule IDs:

RuleDescription
G101Hardcoded credentials
G102Bind to all interfaces (0.0.0.0)
G103Audit unsafe block (use of unsafe package)
G104Unhandled errors
G106SSH InsecureIgnoreHostKey
G107URL with potential SSRF
G201SQL query construction by string concat
G202SQL query construction by string format
G204Subprocess launched with variable
G301Poor file permissions on directory
G302Poor file permissions on file
G303Predictable temp-file name
G304File path traversal vulnerabilities
G305File traversal in tar archive
G401Weak cryptographic algorithms
G402TLS InsecureSkipVerify
G403RSA key length too short
G404Insecure random number generation
G501-G505Insecure crypto primitives (DES, MD5, RC4, SHA1)
G601Implicit memory aliasing in for-range
G602Slice bounds out of range

Full list: gosec subcommand gosec -list-rules.

Step 4 - Output formats

Per gs-gh:

gosec -fmt sarif -out results.sarif ./...
gosec -fmt json -out results.json ./...
gosec -fmt junit-xml -out results.xml ./...
gosec -fmt html -out results.html ./...
gosec -fmt text -out results.txt ./...
gosec -fmt yaml -out results.yaml ./...

For sast-finding-triager integration, use JSON.

Step 5 - False-positive triage (MANDATORY)

Per gs-gh the canonical inline suppression syntax:

// #nosec G404 -- justification text

Format: #nosec [RuleList] [-- Justification].

Three suppression layers:

MechanismExampleWhen to use
Per-line #nosec// #nosec G101 -- test fixture; not deployed to prodSingle-line exception with justification
Per-rule list #nosec// #nosec G104,G115 -- intentional in this fast-pathMulti-rule single-line
-exclude= flaggosec -exclude=G104 ./...Project-wide rule disable (CI flag)
-confidence= filtergosec -confidence=high ./...Triage workflow: only high-confidence first

Justification template (mandatory in code):

// #nosec G401 -- Reason: legacy MD5 required for vendor-mandated checksum format
// Reviewer: alice@example.com (2026-05-15)
// Expires: 2026-12-15
hash := md5.Sum(data)

Bandit-style cadence: every quarter, grep for #nosec patterns lacking -- Reason: and flag for review.

Step 6 - golangci-lint integration

Most Go teams run gosec via golangci-lint (the universal linter runner) rather than directly:

# .golangci.yml
linters:
  enable:
    - gosec

linters-settings:
  gosec:
    excludes:
      - G104                     # unhandled errors (often noise)
    severity: medium
    confidence: medium
    config:
      G306: "0644"               # default file perm threshold
golangci-lint run ./...

This is the recommended pattern - golangci-lint handles parallelism, caching, and unified output across multiple linters.

Step 7 - CI integration

Standalone:

jobs:
  gosec:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v5
        with: { go-version: '1.22' }
      - uses: securego/gosec@master
        with:
          args: -fmt sarif -out gosec.sarif ./...
      - uses: github/codeql-action/upload-sarif@v3
        if: always()
        with: { sarif_file: gosec.sarif }

Via golangci-lint (preferred):

jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v5
        with: { go-version: '1.22' }
      - uses: golangci/golangci-lint-action@v6
        with:
          version: latest

Step 8 - Custom rules via Go templates

Unlike Semgrep / CodeQL, gosec doesn't have a custom-rule DSL - adding new rules requires writing Go code in gosec/rules/ and contributing upstream OR forking. For most teams, leverage the 40+ built-in rules + suppressions.

Anti-patterns

Anti-patternWhy it failsFix
#nosec without rule IDSuppresses ALL rules on that line// #nosec G401 (specific, Step 5)
#nosec without -- JustificationNo audit trailRequired template (Step 5)
Skip -confidence= filterLOW confidence drowns the team-confidence=high for triage (Step 2)
Run gosec separately from golangci-lintTwo linters with different configgolangci-lint integration (Step 6)
Exclude G104 globallyLoses entire "unhandled errors" coveragePer-call // #nosec G104 -- intentional

Limitations

  • Go-only; for other languages see sister skills.
  • Custom-rule authoring requires Go programming + upstream PR (vs YAML rule authoring in Semgrep).
  • Some patterns (cross-package taint flow) miss what codeql-queries catches.
  • Rule depth varies - newer Go patterns (generics, structured concurrency) coverage thinner.

References