How to Correct Firefox’s SSL_ERROR_NO_CYPHER_OVERLAP

How to Correct Firefox's SSL_ERROR_NO_CYPHER_OVERLAP

Here we can see, “How to Correct Firefox’s SSL_ERROR_NO_CYPHER_OVERLAP”


The SSL_ERROR_NO_CYPHER_OVERLAP problem only occurs in Firefox. The warning is “ERR SSL VERSION OR CIPHER MISMATCH” in Google Chrome.

In short, this error happens when Firefox cannot receive security data from a website. It arises when an outdated website lacks updated Secure Sockets Layer (SSL) protection.

SSL is the encryption between your machine and a website’s server. This error means your browser couldn’t safely connect between them. SSL is similar to Transport Layer Security (TLS), which will be discussed shortly.

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  • Firefox may show you that the “authenticity of the data cannot be verified” along with the error message. It may also direct you to contact the website’s owner. While the issue may be with the website, it may also be with the browser.
  • It’s possible that your browser’s version or a specific browser setting is interfering with the website’s contact with your computer. TLS or SSL3 settings may also be disabled or misconfigured.
  • To connect, your browser and the server must both use the same encryption cypher. Due to security issues, mainstream browsers no longer support RC4. This error may occur if the website’s server implements an unsupported encryption mechanism.

This problem has been reported after installing Cloudflare. The browser doesn’t support Cloudflare’s Server Name Indication (SNI) protocol.


Now that we have a better grasp of the issue, we can begin to address it. Here are three possible solutions to the SSL_ERROR_NO_CYPHER_OVERLAP problem in Firefox.

1. Update Firefox

To repair this problem, first, make sure you’re running the latest version of Firefox. This should be done often to maintain your internet experience as smooth as possible.

  1. Open Firefox, click the hamburger menu symbol, then select Help > About Firefox:
  2. If any updates are available, Firefox should start downloading them:
  3. After the download is finished, click Restart to Update Firefox:
  4. You can also grab the newest version from the Firefox website. Remember to uninstall your current version before downloading.
  5. On Windows, press Windows + R, then type “appwix.cpl” into the search box. Locate Firefox in the programme manager and click Uninstall.
  6. Then select Go > Applications from the toolbar. Then erase Mozilla Firefox by dragging it to the trash.

2. Reset TLS and SSL3

If refreshing Firefox didn’t help, you might try resetting your TLS and SSL3 settings. Some websites require these protocols, and if yours are deactivated, you may be receiving the “SSL_ERROR_NO_CYPHER_OVERLAP” error.

  1. Click on a new tab in Firefox and put “about:config” into the address box. “This may void your warranty!” it may say. or “Be Careful”:
  2. This warning is intended to prevent you from mistakenly changing crucial browser settings. Accept the risk and proceed.
  3. Then on the Advanced Preferences screen, type “tls”.
  4. This will show you all your TLS configurations.
  5. Look for values that have changed recently and are bolded. To reset any bolded values, right-click on them and select Reset.
  6. Replicate the process for SSL3. Then, reset any recently changed value with the search bar.
  7. Also, set the following entries to false:
  • security.ssl3.dhe_rsa_aes_128_sha
  • security.ssl3.dhe_rsa_aes_256_sha

Securing these settings is critical.

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3. Override Security Protocols and Browser Settings

  • We don’t encourage bypassing browser security protocols because they protect you from hazardous websites. If you know the site you’re trying to access is safe, you can manually enter a cypher validation to avoid the problem.
  • Return to the about:config screen in Firefox. Type “tls” into the search bar again. Locate security.tls.version.min:
  • To edit the item, click the pencil symbol to the far right and enter “0”. Replicate the process for security. tls.version.fallback-limit.
  • You can also escape encryption by altering your browser’s privacy settings. To do so, go to Firefox > Options > Privacy & Security:
  • Deselect Block hazardous and deceptive content.

Hopefully, you’ve now rectified the error. If not, it’s likely a server-side issue. This usually happens when a site exclusively uses RC4 cyphers.

Due to security issues, major browsers no longer support some cyphers, like RC4. You may examine your SSL certificate’s cyphers with an SSL check.

If you are not the site owner, contact them to let them know about the issue.

User Questions:

How to fix the SSL_ERROR_NO_CYPER_OVERLAP error?

  1. Update Firefox. Updating Firefox is simple.
  2. Reset SSL3 and TLS.
  3. Bypass Your Browser’s Security Protocols.

How to fix a secure connection in Firefox.

  1. Firefox. Enter about:config in the address bar.
  2. The warning page appears. Click on I accept the risk.
  4. Reconnect to the website to see if the issue has gone.

Ssl error no cypher overlap

It is unique among browser errors in that it only occurs in Firefox. SSL is the encryption between your machine and a website’s server, and this error means your browser couldn’t safely connect between them.

How to enable sslv3 in Mozilla?

  1. New Firefox tab
  2. Type about:config in the address bar.
  3. Could you take it?
  4. Then type security.tls in the search bar. Delete security.tls.version.min. Then reduce the value from 1 to 0. Set unrestricted rc4 fallback to true.
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SSLV3 deactivate in Firefox

  1. Type “about:config” in Firefox’s address bar.
  2. Typing “TLS” in the search
  3. Ctrl + a
  4. Enter 1.1 in the integer value field.
  5. OK.

How to fix SSL connection error

  1. Set Your Device’s Date & Time.
  2. Clear Google Chrome’s History.
  3. Reset Your Network.
  4. Stop your antivirus.
  5. App/Browser Update
  6. Visit a website incognito/private.
  7. Clear Data.