VNX-SEC-080: GitHub OAuth / App / Refresh token

Reports a whole GitHub OAuth (gho_), App user-to-server (ghu_), installation (ghs_) or refresh (ghr_) token in any file, excluding classic and fine-grained PATs, prefix lists, truncated tokens, placeholders and test files.

Field	Value
Rule ID	`VNX-SEC-080`
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` `github` `oauth` `credentials`
Source	`internal/sast/rules/vnx-sec-080.rego`

Overview

This rule reports a GitHub OAuth access token (gho_), GitHub App user-to-server token (ghu_), App installation token (ghs_) or refresh token (ghr_, 36 or 76 characters), quoted, assigned, in an Authorization header or inside a clone URL. The token is redacted in the finding’s snippet.

Why This Matters

Hardcoded github oauth / app / refresh token 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.

What Gets Flagged

# FLAGGED: installation token inside a clone URL
git clone https://x-access-token:ghs_<36 characters>@github.com/acme/infra.git

// FLAGGED: refresh token committed with a session file
{ "refresh_token": "ghr_<76 characters>" }

Not flagged:

Classic ghp_ and fine-grained github_pat_ tokens (VNX-SEC-004 and VNX-SEC-079 report them).
Prefix lists and regular expressions ("gho_", "ghs_"), truncated tokens (ghs_16C7e42F... from the GitHub documentation is 32 characters) and placeholders (gho_xxxx...).
Environment references (os.environ["GITHUB_TOKEN"]).
Test, fixture, vendored and generated files.

VNX-SEC-004 also reports these tokens as part of its wider set.

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-080
// nosec vnx-sec-080

Or record an ignore rule: vulnetix ignore add --rule vnx-sec-080 --reason "...". See Suppressing findings.