How to access ssl certificate content using chrome puppeteer

Question

I would like to access certificate details of a url using chrome puppeteer. Is it possible to do it with current puppeteer API?

Answer 1

You can access the DER-encoded certificate using the Chrome DevTools Protocol Network.getCertificate method:

const certificate = await page._client.send('Network.getCertificate', {
  origin: 'https://example.com/',
});

for (let i = 0; i < certificate.tableNames.length; i++) {
  console.log(certificate.tableNames[i]);
}

Answer 2

As Grant Miller said, you can access the full DER-encoded certificate using the Chrome DevTools Protocol Network.getCertificate method, instead of just the securityDetails a puppeteer response provices.

page.on('response', async (res) => {
  if (res.securityDetails() != null) {
    console.info(await page._client.send('Network.getCertificate', {origin: res.url()}));
    /*
      { tableNames: [ 'MIIDwTCCAqmgAwIBAgIJALzkRqUOhsraM...' ] }
      Network.getCertificate - Returns the DER-encoded certificate
    */
  }
}

You can then use any node package to parse each certificate from the encoded certificate chain.