Summary
facebook/react/feature-flags v was classified as CRITICAL RISK with a risk score of 3517. Sigil detected 292 findings across 6882 files, covering phases including provenance, network exfiltration, code patterns, install hooks, credential access, obfuscation. Review the findings below before installing this package.
v
10 April 2026, 16:56 UTC
by Sigil Bot
Risk Score
3517
Findings
292
Files Scanned
6882
Provenance
Repository
https://github.com/facebook/reactScanned From
https://github.com/facebook/react.gitFindings by Phase
Phase Ordering
Phases are ordered by criticality, with the most dangerous at the top. Click any phase header to expand or collapse its findings. Critical phases are expanded by default.
install-npm-postinstall
CRITICALnpm lifecycle script — runs automatically on install
repo/compiler/apps/playground/package.json:10
"postbuild": "node ./scripts/downloadFonts.js",
"preinstall": "cd ../.. && yarn install --frozen-lockfile",
"postinstall": "./scripts/link-compiler.sh",Why was this flagged?
npm lifecycle scripts like postinstall run automatically during package installation with no user interaction required. This is the #1 attack vector for malicious npm packages — attackers embed data theft or backdoor installation in these hooks. Rated CRITICAL because code executes before the developer can review it.
install-npm-postinstall
CRITICALnpm lifecycle script — runs automatically on install
repo/compiler/apps/playground/package.json:11
"preinstall": "cd ../.. && yarn install --frozen-lockfile",
"postinstall": "./scripts/link-compiler.sh",
"vercel-build": "yarn build",Why was this flagged?
npm lifecycle scripts like postinstall run automatically during package installation with no user interaction required. This is the #1 attack vector for malicious npm packages — attackers embed data theft or backdoor installation in these hooks. Rated CRITICAL because code executes before the developer can review it.
install-npm-postinstall
CRITICALnpm lifecycle script — runs automatically on install
repo/compiler/packages/react-forgive/package.json:45
"package": "rm -f react-forgive-0.0.0.vsix && vsce package --yarn",
"postinstall": "cd client && yarn install && cd ../server && yarn install && cd ..",
"pretest": "yarn run build:compiler && yarn run compile && yarn run lint",Why was this flagged?
npm lifecycle scripts like postinstall run automatically during package installation with no user interaction required. This is the #1 attack vector for malicious npm packages — attackers embed data theft or backdoor installation in these hooks. Rated CRITICAL because code executes before the developer can review it.
install-npm-postinstall
CRITICALnpm lifecycle script — runs automatically on install
repo/compiler/packages/snap/package.json:12
"scripts": {
"postinstall": "./scripts/link-react-compiler-runtime.sh && perl -p -i -e 's/react\\.element/react.transitional.element/' ../../node_modules/fbt/lib/FbtReactUtil.js && perl -p -i -e 's/didWarnAboutUsingAct = false;/didWarnAboutUsingAct = true;/' ../../node_modules/react-dom/cjs/react-dom-test-utils.development.js",
"build": "rimraf dist && concurrently -n snap,runtime \"tsc --build\" \"yarn --silent workspace react-compiler-runtime build\"",Why was this flagged?
npm lifecycle scripts like postinstall run automatically during package installation with no user interaction required. This is the #1 attack vector for malicious npm packages — attackers embed data theft or backdoor installation in these hooks. Rated CRITICAL because code executes before the developer can review it.
install-npm-postinstall
CRITICALnpm lifecycle script — runs automatically on install
repo/fixtures/nesting/package.json:10
"scripts": {
"postinstall": "run-p install:*",
"install:legacy": "cd src/legacy && npm install",Why was this flagged?
npm lifecycle scripts like postinstall run automatically during package installation with no user interaction required. This is the #1 attack vector for malicious npm packages — attackers embed data theft or backdoor installation in these hooks. Rated CRITICAL because code executes before the developer can review it.
install-npm-postinstall
CRITICALnpm lifecycle script — runs automatically on install
repo/package.json:138
"extract-errors": "node scripts/error-codes/extract-errors.js",
"postinstall": "node ./scripts/flow/createFlowConfigs.js",
"test": "node ./scripts/jest/jest-cli.js",Why was this flagged?
npm lifecycle scripts like postinstall run automatically during package installation with no user interaction required. This is the #1 attack vector for malicious npm packages — attackers embed data theft or backdoor installation in these hooks. Rated CRITICAL because code executes before the developer can review it.
Badge
Markdown
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