SSL certificate_verify_failed errors typically occur as a result of outdated Python default certificates or invalid root certificates. We will cover how to fix this issue in 4 ways in this article.
Why certificate_verify_failed happen?
The SSL connection will be established based on the following process. We will get errors if any of these steps does not go well.
For this error certificate_verify_failed, it usually happens during step 2 and step 3.
- The client sends a request to the server for a secure session. The server responds by sending its X.509 digital certificate to the client.
- The client receives the server’s X.509 digital certificate.
- The client authenticates the server, using a list of known certificate authorities.
- The client generates a random symmetric key and encrypts it using server’s public key.
- The client and server now both know the symmetric key and can use the SSL encryption process to encrypt and decrypt the information contained in the client request and the server response.
When the client receives the server’s certificate, it begins chaining that certificate back to its root. It will begin by following the chain to the intermediate that has been installed, from there it continues tracing backwards until it arrives at a trusted root certificate.
If the certificate is valid and can be chained back to a trusted root, it will be trusted. If it can’t be chained back to a trusted root, the browser will issue a warning about the certificate.
Related: Check SSL Certificate Chain with OpenSSL Examples
Error info about certificate_verify_failed
We will see the following error.
<urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:777)>
Here is a detailed post about how to check SSL certificate.
What is SSL certificate
Server certificates are the most popular type of X.509 certificate. SSL/TLS certificates are issued to hostnames (machine names like ‘ABC-SERVER-02’ or domain names like google.com).
A server certificate is a file installed on a website’s origin server. It’s simply a data file containing the public key and the identity of the website owner, along with other information. Without a server certificate, a website’s traffic can’t be encrypted with TLS.
Technically, any website owner can create their own server certificate, and such certificates are called self-signed certificates. However, browsers do not consider self-signed certificates to be as trustworthy as SSL certificates issued by a certificate authority.
Related: 2 Ways to Create self signed certificate with Openssl Command
How to fix certificate_verify_failed?
If you receive the “certificate_verify_failed” error when trying to connect to a website, it means that the certificate on the website is not trusted. There are a few different ways to fix this error.
We will skip the SSL certificate check in the first three solutions. For the fourth solution, we are going to install the latest CA certificate from certifi.
Create unverified context in SSL
import ssl
context = ssl._create_unverified_context()
urllib.request.urlopen(req,context=context)
Create unverified https context in SSL
import ssl
ssl._create_default_https_context = ssl._create_unverified_context
urllib2.urlopen(“https://google.com”).read()
Use requests module and set ssl verify to false
requests.get(url, headers=Hostreferer,verify=False)
Update SSL certificate with PIP
we can also update our SSL certificate With PIP. All we would have to do is to update our SSL certificate directory with the following piece of code: pip install –upgrade certifi
What this command does is update our system’s SSL certificate directory.
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