VNX-SEC-059: Linear API key

Reports a hard-coded Linear personal API key (lin_api_ + 40 alphanumerics) or OAuth access token (lin_oauth_ + 64 hex), but not bare prefixes, placeholders, lookalike identifiers or keys read from the environment.

Field	Value
Rule ID	`VNX-SEC-059`
Severity	Critical
SARIF level	`error`
Kind	`secrets`
Languages	Any file
CWE	CWE-798
CAPEC	CAPEC-191
ATT&CK	T1552.001
CWSS vector	`CWSS:1.0/TI:C/AP:A/AL:A/IC:N/FC:LT/RP:N/RL:A/AV:I/AS:N/IN:A/SC:A/BI:C/DI:H/EX:H/EC:N/P:W`
Tags	`secrets` `linear` `credentials`
Source	`internal/sast/rules/vnx-sec-059.rego`

Overview

This rule reports a Linear credential written into a file: a personal API key (lin_api_ + 40 alphanumerics) or an OAuth access token (lin_oauth_ + 64 hex), standing alone rather than inside a longer identifier and with enough entropy to be real. The snippet is redacted.

It does not report bare prefixes in a prefix check, placeholder bodies (xxxx, YOUR_KEY_HERE), identifiers that merely begin lin_api_, keys read from the environment, or test, fixture and vendored paths.

What Gets Flagged

// FLAGGED: API key passed to the SDK
export const linear = new LinearClient({ apiKey: "lin_api_<40 alphanumerics>" });

# FLAGGED: OAuth token in a workflow
env:
  LINEAR_TOKEN: lin_oauth_<64 hex>

// NOT FLAGGED: read from the environment
export const linear = new LinearClient({ apiKey: process.env.LINEAR_API_KEY });

Why This Matters

Hardcoded linear api key values are routinely scraped by automated bots within minutes of a public push, and then used to access the account, exfiltrate data, or pivot into downstream services. Once the credential is in git history it is permanently in third-party hands.

Remediation

Revoke the leaked credential in the provider’s console immediately.
Replace with a short-lived alternative, OAuth 2.0 access tokens, IAM role assumption, OIDC federation, wherever the platform supports it.
Store the new credential in a secrets manager (AWS Secrets Manager, HashiCorp Vault, GitHub Actions secrets, Doppler).
Audit the provider’s access logs for activity you did not initiate between the leak and the revocation.
Purge from git history with git filter-repo or BFG, then re-scan with gitleaks/truffleHog to confirm no other secrets remain.
Enable push protection so future commits are blocked at the developer machine.

References

Suppressing this rule

Put a nosec comment on the line, or on line 1 to cover the whole file. Use the comment marker of the file’s language (#, //, -- or ;):

# nosec vnx-sec-059
// nosec vnx-sec-059

Or record an ignore rule: vulnetix ignore add --rule vnx-sec-059 --reason "...". See Suppressing findings.