es5-ext
ECMAScript extensions and shims
1
Versions
ISC
License
Yes
Install Scripts
Missing
Provenance
Supply chain provenance
Status for the latest visible version.
No SLSA provenance
npm registry signatures
gitHead linked
Without SLSA provenance there is no cryptographic link between this tarball and the public source — the axios compromise (March 2026) relied on exactly this gap.
Maintainers
medikoo
Keywords
ecmascriptecmascript5ecmascript6es5es6extensionsextaddonsextrasharmonyjavascriptpolyfillshimutilutilsutilities
Accepted risks
Findings the reviewer chose to accept rather than block on.
| Source | Rule | Reason | Accepted by | When |
|---|---|---|---|---|
| install-scripts | install-script:postinstall | AI (install-scripts): es5-ext's postinstall displays an informational message (Ukraine awareness); wrapped in try/catch, non-malicious, well-known in ecosystem. | ai | |
| semgrep | semgrep:new-function-constructor | AI (semgrep): new Function() used to create named function wrappers preserving arity — standard pattern in utility libraries, not arbitrary code execution. | ai | |
| provenance | no-provenance | AI (provenance): No provenance is common (~12% adoption); trusted publisher with long track record. | ai |
Versions (showing 1 of 1)
| Version | Deps | Published |
|---|---|---|
| 0.10.64 | 4 / 10 |
v0.10.64
2 findings
HIGH
Package has 'postinstall' script
install-scripts
Script: node -e "try{require('./_postinstall')}catch(e){}" || exit 0
LOW
No provenance attestation
provenance
Package was published without Sigstore provenance. Only ~12% of npm packages have provenance, so this is common but not ideal.