Secrets Audit — Credential Exposure and Secrets-Management Review
Two halves: (1) find secrets that have already leaked into source, history, or artifacts, and (2) audit the secrets-management posture that determines whether future leaks happen.
Most secret leaks aren't "we forgot to redact" — they're "we never had a system, so every developer made up their own approach." This skill covers both the cleanup and the prevention.
Cross-references:
(CI-related secrets risk in build-time exposure),
(workload identity federation as the alternative to long-lived keys),
A02 (in-source secret patterns).
Part 1 — Find leaked secrets
Provider key prefixes (high-confidence patterns)
The most useful first sweep is grep against known provider key prefixes. False positives are low and matches are almost always real.
bash
# Stripe
grep -rE "(sk_live_|sk_test_|rk_live_|whsec_)[A-Za-z0-9]{20,}" . \
--include="*.{js,ts,jsx,tsx,py,rb,go,java,php,sh,env,yml,yaml,json}"
# AWS access keys
grep -rE "(AKIA|ASIA)[A-Z0-9]{16}" .
# AWS secret keys (40 chars, base64-y) — high FP rate, use with caution
grep -rE "[A-Za-z0-9/+=]{40}" . --include="*.env*" --include="*.json"
# GitHub
grep -rE "gh[pousr]_[A-Za-z0-9]{36}" .
# Google Cloud API key + service-account JSON
grep -rE "AIza[A-Za-z0-9_-]{35}" .
grep -rln '"type": "service_account"' . --include="*.json"
# Slack
grep -rE "xox[baprs]-[A-Za-z0-9-]+" .
# OpenAI / Anthropic
grep -rE "sk-[A-Za-z0-9]{32,}" .
grep -rE "sk-ant-[A-Za-z0-9_-]{90,}" .
# Generic high-entropy strings in env files
grep -rE "^[A-Z_]+=[A-Za-z0-9/+=]{32,}$" . --include="*.env*"
For full repo coverage, use
to scope to tracked files and avoid
:
bash
git ls-files | xargs grep -lE 'sk_live_|ghp_|AKIA[A-Z0-9]{16}|sk-ant-|AIza[A-Za-z0-9_-]{35}' 2>/dev/null
Tooling
| Tool | Use |
|---|
| Fast, low FP, run as pre-commit and in CI; supports custom rules |
| Verifies findings against the real API (high confidence) |
| Yelp's tool; good baseline file workflow |
| GitHub Secret Scanning | Free for public repos; covers most providers automatically; pushes get blocked at push time when enabled with push protection |
| GitLab Secret Detection | Similar, built-in to CI |
| GitGuardian / Doppler / Spectral | Commercial; add organizational dashboards and historical analysis |
Git history (the part people forget)
A secret deleted in the latest commit is still in history —
,
, and any fork or local clone all have it.
bash
# Search every commit for a pattern
git log -p -S "sk_live_" --all
# Search only deleted lines
git log -p --all | grep -E "^-.*sk_live_"
# Trufflehog historical scan
trufflehog git file://. --since-commit=<first-commit>
# Git history rewrite — destructive, coordinate first
git filter-repo --invert-paths --path config/secrets.yml
# or
bfg --delete-files secrets.yml
Critical caveat: rewriting history requires every developer to re-clone, every fork is still exposed, and the secret should be considered compromised regardless. Always rotate first, history-rewrite second.
Build artifacts and other forgotten places
Secrets leak in places that aren't
files:
- Docker images — shows every line; ends up in layers
- CI environment — secrets logged by , , error stack traces, debug output
- Frontend bundles — / / env vars are shipped to the browser; grep the bundled JS
- Crash reports — Sentry / Datadog / Bugsnag capturing snapshots
- Logs — application logs shipped to a SIEM that has weaker access controls than the app
- Backups — of a table that includes user-stored API keys
- Public S3 / blob storage — accidentally uploaded
- Documentation — README.md examples with real keys instead of placeholders
- Slack / Notion / Linear — pasted in a DM "to test," never rotated
- Browser localStorage / cookies — captured in shared screenshots or session replays
Triaging a found secret
When you find a leaked secret:
- Verify it's live — use the provider's verification (
aws sts get-caller-identity
, , curl -H "Authorization: Bearer $TOKEN" ...
) — don't assume; some leaked keys are already revoked or were sandbox-only
- Determine exposure window — first commit it appeared in, when the repo went public, when CI logs were retained from
- Determine blast radius — what does this key access? What can be done with it? IAM permissions, Stripe live vs test, GitHub vs
- Rotate immediately — generate a new key, deploy it, then revoke the old one (revoke-first breaks prod)
- Audit for use — provider audit logs (CloudTrail, GitHub audit log, Stripe events) for any activity from the leaked credential
- Then clean — remove from current code, then optionally history-rewrite (low priority once rotated)
- Document — incident report, even if rotation was clean; recurrence patterns surface trends
Part 2 — Audit secrets-management posture
The hierarchy of secret storage (worst → best)
| Tier | Pattern | When acceptable |
|---|
| ❌ | Hardcoded in source | Never |
| ❌ | Hardcoded in image / build artifact | Never |
| ❌ | Plaintext in shared docs / Slack | Never |
| ⚠️ | file in repo (even with .gitignore — easy to leak via push, backup, archive) | Bootstrap only; flagged in audit |
| ⚠️ | Environment variables (only) | Acceptable for ephemeral dev; weak for prod (visible in /proc, crash dumps, logs) |
| 🟢 | Secrets manager pulled at deploy time | Standard for most apps |
| 🟢 | Workload identity federation (no stored secret at all) | Best where supported |
Cloud-provider secrets managers
- AWS Secrets Manager / Parameter Store (SecureString) — integrate via IAM-scoped IRSA / task role / Lambda role
- GCP Secret Manager — bind via Workload Identity to GSA, GSA pulls secret
- Azure Key Vault — pull via managed identity
- Doppler / Infisical / 1Password Secrets Automation — cross-cloud, developer-friendly
Audit checklist
- No secrets in Git history (run gitleaks --all)
- No committed — covers (with care for )
- Secrets fetched at runtime, not embedded at build — image rebuild is not required to rotate
- IAM scoped to the secret — service A can read secret A, not secret B
- Rotation cadence — defined per secret class (admin: 30d, service: 90d, customer-shared: per breach response)
- Rotation is automated — if a human runs a script every 90 days, rotation will eventually drift
- Access logged — every Get / Decrypt call is in an audit trail
- No long-lived cloud keys for workloads — workload identity federation everywhere it's supported (see )
- Break-glass procedure — when the secrets manager is down, how do critical services come up? (Usually: cached on disk encrypted, with strict re-fetch on restart)
- Cross-environment isolation — staging cannot read prod secrets, ever (different KMS keys, different IAM)
Common findings
- Rotation never tested — secret stores configured, never actually rotated; first attempt breaks prod
- shipped to staging — environment-specific dev secrets cross the boundary
- CI secrets accessible from PRs from forks — GitHub's default behavior was previously dangerous; verify and secret accessibility
- Build args used for secrets —
--build-arg AWS_SECRET=...
ends up in image history (use /BuildKit instead)
- Logging frameworks dump on unhandled exception — Sentry / Datadog / Bugsnag scrub config required
- Secret stored in K8s as plain Secret without etcd encryption — base64 is encoding, not encryption (see )
- OAuth client secrets in mobile apps — public clients can't hold secrets; PKCE is the answer
Output Format
markdown
# Secrets Audit Report
## Scope: [repos / environments / managers covered]
## Date: [date]
### Live leaked secrets found
|---|---|---|---|---|
### Secrets-management posture
|---|---|---|
### Recommendations
| Priority | Item | Owner | Deadline |
|---|---|---|---|
Disposition rule (Fixed / Deferred / Accepted Risk) per
.
Boundaries
- Only audit repositories, CI systems, and infrastructure the user has authorization for
- Never use a found secret to access the provider — verify it's live with a minimal API call (account info, not data extraction); do not pivot
- For history rewrite operations: never proceed without explicit confirmation and a coordinated developer-notification plan
- Refuse to help collect or weaponize leaked secrets found in other people's repos
- If the audit surfaces credentials belonging to a third party (vendor, employee personal accounts), notify and rotate; don't quietly fix
References
- OWASP Cheat Sheet: Secrets Management
- NIST SP 800-57 (Recommendation for Key Management)
- GitGuardian "State of Secrets Sprawl" annual reports — useful for industry context
- , , documentation
- GitHub Secret Scanning + Push Protection documentation
- HashiCorp Vault Architecture / Best Practices
- AWS Secrets Manager Best Practices
- "Twelve-Factor App" — Config principles