Files
everything-claude-code/scripts/ci/validate-workflow-security.js
Jamkris e06d038257 fix(ci): match quoted write-all + dedupe duplicate checkout violations
Two round-1 review findings, fixed together because they touch the
same regex/loop region of `findViolations`:

1. **cubic P0 — quoted write-all bypass**.
   `WRITE_ALL_PATTERN` was `/^\s*permissions:\s*write-all\b/m`, which
   does not match the perfectly valid YAML forms
   `permissions: "write-all"` and `permissions: 'write-all'`. A
   workflow that quoted the shorthand slipped right through the
   persist-credentials gate the previous commit was supposed to close.

   Reproduced before this commit:
     $ cat /tmp/q.yml
     name: bad
     on: [push]
     permissions: "write-all"
     jobs:
       do:
         runs-on: ubuntu-latest
         steps:
           - uses: actions/checkout@v4
     $ ECC_WORKFLOWS_DIR=/tmp node scripts/ci/validate-workflow-security.js
     Validated workflow security for 1 workflow files
     exit=0

   Fix: tighten the regex to
     /^\s*permissions:\s*["']?write-all["']?\s*$/m
   which accepts the bare, double-quoted, and single-quoted YAML forms
   while still anchoring on the `permissions:` key. The trailing `\s*$`
   prevents accidentally matching keys whose value happens to start
   with `write-all` (e.g. some future literal `write-all-something`).

2. **greptile P2 — duplicate violation when both patterns match**.
   A `ref: refs/pull/${{ github.event.pull_request.head.sha }}/merge`
   value matches both the `pull_request_target` rule's
   `expressionPattern` (the `head.sha` interpolation) and its
   `refPattern` (the `refs/pull/` literal). Each push generates an
   ERROR line with the same description and just a different
   `expression:` echo, so the reviewer sees the same violation twice.

   Fix: track `stepFlagged` inside the per-step loop and skip the
   `refPattern` fallback once any `expressionPattern` match has already
   produced a violation for this step. The `refPattern` is a fallback
   for ref-only forms (`refs/pull/123/head`, `${{ env.X }}` whose
   resolved value is a PR ref); when the more specific expression
   already fires, the fallback is redundant by definition.

After both fixes, the round-1 reproductions resolve cleanly:

  $ # quoted form now blocks
  $ ECC_WORKFLOWS_DIR=/tmp/q1/.github/workflows node scripts/ci/validate-workflow-security.js
  ERROR: quoted.yml:8 - workflows with write permissions must disable checkout credential persistence
  exit=1

  $ # combined head.sha + refs/pull now prints one ERROR, not two
  $ ECC_WORKFLOWS_DIR=/tmp/q2/.github/workflows node scripts/ci/validate-workflow-security.js
  ERROR: dup.yml:10 - pull_request_target must not checkout an untrusted pull_request head ref/repository
    Unsafe expression: ${{ github.event.pull_request.head.sha }}
  exit=1

Test additions land in the next commit.
2026-05-17 21:19:29 -04:00

266 lines
9.1 KiB
JavaScript

#!/usr/bin/env node
/**
* Reject unsafe GitHub Actions patterns that execute or checkout untrusted PR code
* from privileged events such as workflow_run or pull_request_target.
*/
const fs = require('fs');
const path = require('path');
const DEFAULT_WORKFLOWS_DIR = path.join(__dirname, '../../.github/workflows');
const RULES = [
{
event: 'workflow_run',
eventPattern: /\bworkflow_run\s*:/m,
description: 'workflow_run must not checkout an untrusted workflow_run head ref/repository',
expressionPattern: /\$\{\{\s*github\.event\.workflow_run\.(?:head_branch|head_sha|head_repository(?:\.[A-Za-z0-9_.]+)?)\s*\}\}|\$\{\{\s*github\.event\.workflow_run\.pull_requests\[\d+\]\.head\.(?:ref|sha|repo\.full_name)\s*\}\}/g,
},
{
event: 'pull_request_target',
eventPattern: /\bpull_request_target\s*:/m,
description: 'pull_request_target must not checkout an untrusted pull_request head ref/repository',
expressionPattern: /\$\{\{\s*github\.event\.pull_request\.head\.(?:ref|sha|repo\.full_name)\s*\}\}/g,
// Even without the standard `github.event.pull_request.head.*` expression,
// a checkout under `pull_request_target` that fetches a `refs/pull/<N>/{head,merge}`
// ref pulls attacker-controlled code into a workflow with write-scoped
// tokens. GitHub's security guidance treats both forms equivalently;
// we match the ref value directly so any interpolation that resolves
// to such a ref (`refs/pull/${{ github.event.pull_request.number }}/merge`,
// a hardcoded `refs/pull/123/head`, a `${{ env.X }}` that the maintainer
// assumes is safe, etc.) trips the same rule.
refPattern: /^\s*ref:\s*['"]?[^'"\n]*refs\/(?:remotes\/)?pull\/[^'"\n\s]+/m,
},
];
const WRITE_PERMISSION_PATTERN = /^\s*(?:contents|issues|pull-requests|actions|checks|deployments|discussions|id-token|packages|pages|repository-projects|security-events|statuses):\s*write\b/m;
// `permissions: write-all` is GitHub Actions' shorthand for granting every
// scope write access. The named-scope pattern above misses it because there
// is no scope name on the left of the colon — just the literal `write-all`
// value at the permissions key. Treat both as equivalent for the purposes
// of the persist-credentials gate below. The optional single/double quotes
// match valid YAML `permissions: "write-all"` / `'write-all'` forms.
const WRITE_ALL_PATTERN = /^\s*permissions:\s*["']?write-all["']?\s*$/m;
const NPM_AUDIT_PATTERN = /\bnpm\s+audit\b(?!\s+signatures\b)/;
const NPM_AUDIT_SIGNATURES_PATTERN = /\bnpm\s+audit\s+signatures\b/;
const ACTIONS_CACHE_PATTERN = /uses:\s*['"]?actions\/cache@/m;
const ID_TOKEN_WRITE_PATTERN = /^\s*id-token:\s*write\b/m;
const UNSAFE_INSTALL_PATTERNS = [
{
pattern: /\bnpm\s+ci\b(?![^\n]*--ignore-scripts)/g,
description: 'npm ci must include --ignore-scripts',
},
{
pattern: /\bpnpm\s+install\b(?![^\n]*--ignore-scripts)/g,
description: 'pnpm install must include --ignore-scripts',
},
{
pattern: /\byarn\s+install\b(?![^\n]*--mode=skip-build)/g,
description: 'yarn install must use --mode=skip-build',
},
{
pattern: /\bbun\s+install\b(?![^\n]*--ignore-scripts)/g,
description: 'bun install must include --ignore-scripts',
},
];
function getWorkflowFiles(workflowsDir) {
if (!fs.existsSync(workflowsDir)) {
return [];
}
return fs.readdirSync(workflowsDir)
.filter(file => /\.(?:yml|yaml)$/i.test(file))
.map(file => path.join(workflowsDir, file))
.sort();
}
function getLineNumber(source, index) {
return source.slice(0, index).split(/\r?\n/).length;
}
function extractCheckoutSteps(source) {
const blocks = [];
const lines = source.split(/\r?\n/);
let current = null;
for (let i = 0; i < lines.length; i++) {
const line = lines[i];
const stepStart = line.match(/^(\s*)-\s+/);
if (stepStart) {
if (current) {
blocks.push(current);
}
current = {
indent: stepStart[1].length,
startLine: i + 1,
lines: [line],
};
continue;
}
if (current) {
current.lines.push(line);
}
}
if (current) {
blocks.push(current);
}
return blocks
.map(block => ({
startLine: block.startLine,
text: block.lines.join('\n'),
}))
.filter(block => /uses:\s*['"]?actions\/checkout@/m.test(block.text));
}
function findViolations(filePath, source) {
const violations = [];
const checkoutSteps = extractCheckoutSteps(source);
for (const rule of RULES) {
if (!rule.eventPattern.test(source)) {
continue;
}
for (const step of checkoutSteps) {
// Track whether the expression-based rule already produced a
// violation for this step. If it did, skip the refPattern fallback
// — a `refs/pull/${{ github.event.pull_request.head.sha }}/merge`
// value matches both patterns under the same rule, and the second
// push would print a duplicate ERROR line that says exactly the
// same thing with a different `expression:` echo.
let stepFlagged = false;
for (const match of step.text.matchAll(rule.expressionPattern)) {
violations.push({
filePath,
event: rule.event,
description: rule.description,
expression: match[0],
line: step.startLine + getLineNumber(step.text, match.index) - 1,
});
stepFlagged = true;
}
if (rule.refPattern && !stepFlagged) {
const refMatch = step.text.match(rule.refPattern);
if (refMatch) {
violations.push({
filePath,
event: rule.event,
description: rule.description,
expression: refMatch[0].trim(),
line: step.startLine + getLineNumber(step.text, refMatch.index) - 1,
});
}
}
}
}
if (WRITE_PERMISSION_PATTERN.test(source) || WRITE_ALL_PATTERN.test(source)) {
for (const step of checkoutSteps) {
if (!/persist-credentials:\s*['"]?false['"]?\b/m.test(step.text)) {
violations.push({
filePath,
event: 'write-permission checkout',
description: 'workflows with write permissions must disable checkout credential persistence',
expression: 'actions/checkout without persist-credentials: false',
line: step.startLine,
});
}
}
}
for (const installRule of UNSAFE_INSTALL_PATTERNS) {
for (const match of source.matchAll(installRule.pattern)) {
violations.push({
filePath,
event: 'dependency install scripts',
description: `workflow dependency installs must not run lifecycle scripts: ${installRule.description}`,
expression: match[0],
line: getLineNumber(source, match.index),
});
}
}
if (ID_TOKEN_WRITE_PATTERN.test(source) && ACTIONS_CACHE_PATTERN.test(source)) {
violations.push({
filePath,
event: 'id-token cache',
description: 'workflows with id-token: write must not restore or save shared dependency caches',
expression: 'id-token: write + actions/cache',
line: getLineNumber(source, source.search(ID_TOKEN_WRITE_PATTERN)),
});
}
if (ACTIONS_CACHE_PATTERN.test(source)) {
violations.push({
filePath,
event: 'dependency cache',
description: 'GitHub Actions dependency caches are disabled during active supply-chain hardening',
expression: 'actions/cache',
line: getLineNumber(source, source.search(ACTIONS_CACHE_PATTERN)),
});
}
if (/\bpull_request_target\s*:/m.test(source) && ACTIONS_CACHE_PATTERN.test(source)) {
violations.push({
filePath,
event: 'pull_request_target cache',
description: 'pull_request_target workflows must not restore or save shared dependency caches',
expression: 'pull_request_target + actions/cache',
line: getLineNumber(source, source.search(/\bpull_request_target\s*:/m)),
});
}
if (NPM_AUDIT_PATTERN.test(source) && !NPM_AUDIT_SIGNATURES_PATTERN.test(source)) {
violations.push({
filePath,
event: 'npm audit signatures',
description: 'workflows that run npm audit must also verify registry signatures',
expression: 'npm audit without npm audit signatures',
line: getLineNumber(source, source.search(NPM_AUDIT_PATTERN)),
});
}
return violations;
}
function validateWorkflowSecurity(workflowsDir = DEFAULT_WORKFLOWS_DIR) {
const files = getWorkflowFiles(workflowsDir);
const violations = [];
for (const filePath of files) {
const source = fs.readFileSync(filePath, 'utf8');
violations.push(...findViolations(filePath, source));
}
if (violations.length > 0) {
for (const violation of violations) {
console.error(
`ERROR: ${path.basename(violation.filePath)}:${violation.line} - ${violation.description}`,
);
console.error(` Unsafe expression: ${violation.expression}`);
}
return 1;
}
console.log(`Validated workflow security for ${files.length} workflow files`);
return 0;
}
if (require.main === module) {
process.exit(validateWorkflowSecurity(process.env.ECC_WORKFLOWS_DIR || DEFAULT_WORKFLOWS_DIR));
}
module.exports = {
DEFAULT_WORKFLOWS_DIR,
extractCheckoutSteps,
findViolations,
validateWorkflowSecurity,
};