I am using Chrome 61.0.3163.100 and Firefox 39 on Windows 7 32-bit with Burp Suite v1.7.

I have imported latest CA certificate for Burp Suite. In spite of which it's not working for sites with HSTS and throwing following error in Chrome.


CA certificate

In Firefox its showing following error:

An error occurred during a connection to www.google.co.in. SSL received a weak ephemeral Diffie-Hellman key in Server Key Exchange handshake message. (Error code: ssl_error_weak_server_ephemeral_dh_key)

I have checked following sources:

Make SSL work with Chrome (yes, I read the installation procs)

Securing a Web application using HSTS

Burp Suite - Although my configurations are correct, still Chrome doens't allows me to access HTTPS sites and throws an error!

What am I missing ?

  • "I have checked multiple sources but I didn't found a clear solution to this." - or in other words: "I've looked around but will not tell you what I saw and tried and how I failed. Figure out yourself what my problem is.". Oct 25, 2017 at 18:27
  • @SteffenUllrich: Thanks for the downvote. I have updated my answer.
    – Rahul
    Oct 25, 2017 at 18:50
  • much better now. Oct 25, 2017 at 19:04
  • I see you've upgraded Burp. Did you already install the Burp CA in your browser? If you did, you may need to remove it and try again. Please following the certificate installation instructions precisely. Also, I think your question is not a good fit for Stack Exchange, but we're happy to help if you email [email protected] Oct 26, 2017 at 8:10
  • @PortSwigger: I have installed CA after upgrading Burp. I have followed all instructions carefully. Like I mentioned there is thread with same issue but it ain't solved yet.
    – Rahul
    Oct 26, 2017 at 8:59

2 Answers 2


You get this error because Chrome expects a subject alternative name, as correctly stated in of the sources you've checked. This problem was fixed in Burp already. From the release notes for Burp version 1.7.20.

Burp Proxy's generated per-host SSL certificates now include the site's commonName in the subjectAlternativeName extension. Apparently fallback to the commonName was deprecated by RFC2818 (in 2000), and browsers have recently decided to implement this.

But, you are using an older version.

I am using Chrome 61.0.3163.100 on Windows 7 32-bit with Burp Suite v1.6.

Thus, you need to use at least version 1.7.20 to have this problem fixed.

  • I have downloaded version 1.7.27 but still the problem persists.
    – Rahul
    Oct 25, 2017 at 21:08
  • @Rahul: in this case please provide the certificate you've got in the browser (the part you've whitened out in your post, i.e. from ----- BEGIN CERTIFICATE... until the END CERTIFICATE) so that one can have a closer look of what you actually get. Please check also that the error you've got after the upgrade of Burp is still the same ERR_CERT_COMMON_NAME_INVALID and not some other one (like invalid issuer - in which case the proxy CA from Burp might have changed). Oct 26, 2017 at 1:36
  • Updated my question.
    – Rahul
    Oct 26, 2017 at 6:18
  • @Rahul: please provide the certificate as text and not as image so that one can feed it into tools for analysis. Also, you can see that the error is now different: it complains that the issuer is now untrusted - probably because you have a new proxy CA in Burp now. You need to add this new CA as trusted into your browser. Oct 26, 2017 at 6:22
  • 1
    Nice to see someone reading the release notes :) Oct 26, 2017 at 8:11

It seems that you are using proxy that inspects HTTPS data. Your proxy generates certificates to supply to clients. However, these certificates are not compatible with Google Chrome, because they contain Subject field, but do not contain Subject Alternative Names (SAN) certificate extension. I'm not familiar with this software, so there are available options to you:

  • configure your proxy (if such option ever exist) to generate a SAN extension along with filling Subject field
  • change your web browser
  • contact vendor support (PortSwigger) to resolve the issue
  • change proxy software to compatible with Chrome.
  • In my updated question I have mentioned a source having discussion about same issue. It's incomplete and problem is still unsolved.
    – Rahul
    Oct 25, 2017 at 18:56
  • Why not to contact PortSwigger support directly?
    – Crypt32
    Oct 25, 2017 at 18:58
  • Like I said there is already a question being asked on same issue but discussion is not complete/problem is not solved.
    – Rahul
    Oct 25, 2017 at 19:00
  • Ok, can you post certificate you are receiving from Burp?
    – Crypt32
    Oct 25, 2017 at 19:02
  • You mean the file ? How is it relevant ?
    – Rahul
    Oct 25, 2017 at 19:15

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .