The ERR_SSL_VERSION_OR_CIPHER_MISMATCH error occurs on Chromium-based browsers like Google Chrome and Microsoft Edge. On Firefox, you’ll encounter the SSL_ERROR_NO_CYPHER_OVERLAP error instead.
Regardless of the exact error code, the main reason you encounter this error is that the web server you’re trying to access uses outdated and insecure configurations like SSL or RC4.
As such, this issue can only be ‘fixed’ from the backend, but that’s not to say users can’t do anything about this. We’ve also detailed ways for users to bypass the error if you require it in this article.
What Causes This SSL Error?
Ways to Fix ERR_SSL_VERSION_OR_CIPHER_MISMATCH
Since the actual problem is with the ciphers used on the server side, the proper fix is to set up the web server correctly, so we’ve listed it first. But as this backend fix won’t be applicable to normal users, we’ve also listed other ways further in the article to fix or bypass this error in case of client-side issues.
Resolve Server-End Issues
If you aren’t already aware of your web server configurations, you may check them by pressing thepadlockicon in the URL bar and selectingConnection is secure > Certificate is valid.
In the General and Details tabs, you may check the SSL Certificate Common Name, SSL Version, Certificate Signature Algorithm, and more. If you perform an online SSL test, you’ll receive even more info in an easy-to-digest form.
Regardless of how you check the configurations, though, the important thing is to ensure that your server doesn’t support an outdated TLS version or encryption method. You should also ensure that there isn’t a certificate name mismatch issue.
Depending on the CDN you’re using, there may be some misconfigured SSL-related settings that are leading to this error. For instance, in the case of Cloudflare, you need to turn on theDisable Universal SSLoption to resolve this error.
Most browsers don’t support outdated configurations like TLS 1.0 or non-HTTPS connections for a good reason. But there are some cases where you must access the site despite the security risk. For instance, you may need to access an old router or a WiFi device. In such cases, there are a few things you may do.
On Chrome, you may typethisisunsafe(all lowercase and no spaces) )while on the warning page to bypass the error and access the site.
The SSL Version Or Cipher Mismatch error is often limited to a specific browser. So, your second option is to try accessing the site with a different browser.
The third option, which ties into the previous one, is to use an old version of the browser. The reason switching browser works is that often, the secondary browser is outdated and still supports insecure configurations, which ultimately allows you to access the website.
