Sensitive data must be protected when transmitted over the network. This data may include user credentials and credit card information. Servers are authenticated using digital certificates. These are SSL/TLS certificates.
TLS encrypts communication between servers and web applications, such as web browsers that load a website. TLS uses one or more cipher suites to protect data transfer, a combination of authentication or encryption.
How to Detect Weak SSL/TLS?
There are some websites to check TLS version.
In addition, version info can be found using terminal.
This command line is used in order to find TLS version.
Nmap -sV –script ssl-enum-ciphers -p <port number> <Host>
As seen below, Here is the TLS versions.
What does this information do?
TLS 1.0, TLS 1.1, TLS 1.2 and SSLv3 are weak SSL algorithms. Using outdated or outdated versions can make it vulnerable to attacks. When using an insufficient password, an attacker can intercept or modify the data being transferred.
However, 64-bit block ciphers are also weak SSL ciphers. The use of 64-bit block ciphers can cause a SWEET32 attack.
Mitigation and Remediation
- TLS 1.2 and below should be avoided. TLS 1.3, the most secure and up-to-date version of TLS, should be used.
References:
https://owasp.org/www-project-web-security-testing-guide/01-Testing_for_Weak_SSL_TLS_Ciphers
https://nmap.org/nsedoc/scripts/ssl-enum-ciphers.html
https://www.rapid7.com/blog/post/2018/03/29/how-to-detect-weak-ssl-tls-encryption/
https://support.securityscorecard.com/hc/en-us/articles/115003260246-TLS-Protocol-Uses-Weak-Cipher
FAQs
TLS 1.0, TLS 1.1, TLS 1.2 and SSLv3 are weak SSL algorithms. Using outdated or outdated versions can make it vulnerable to attacks. When using an insufficient password, an attacker can intercept or modify the data being transferred. However, 64-bit block ciphers are also weak SSL ciphers.
What are the risks of weak SSL ciphers? ›
Successful brute-forcing of weak ciphers can result in a malicious actor decrypting data containing sensitive information, potentially leading to a complete compromise of confidentiality and integrity.
How to fix weak SSL ciphers? ›
- Backup your ssl.conf. Connect to your server and make a copy of your ssl.conf incase you need to revert it: cp /etc/nginx/common/ssl.conf /etc/nginx/common/ssl.conf.backup.
- Edit the ssl. conf and remove weak ciphers. ...
- Ensure your changes persist. ...
- Check and reload Nginx.
SSL version 1 and 2, SSLv2 and SSLv3 are now insecure. It is also recommended to phase out TLS 1.0 and TLS 1.1. We recommend that you disable SSLv2, SSLv3, TLS 1.0 and TLS 1.1 in your server configuration so that only the newer TLS protocols can be used. It is recommended to only enable TLS 1.3 for maximum security.
What is insecure transport weak SSL cipher? ›
Use of an insecure version of TLS/SSL weakens the data protection strength and might allow an attacker to compromise, steal, or modify sensitive information. Weak versions of TLS/SSL might exhibit one or more of the following properties: - No protection against man-in-the-middle attacks.
What are the weak SSL algorithms? ›
TLS 1.0, TLS 1.1, TLS 1.2 and SSLv3 are weak SSL algorithms. Using outdated or outdated versions can make it vulnerable to attacks. When using an insufficient password, an attacker can intercept or modify the data being transferred. However, 64-bit block ciphers are also weak SSL ciphers.
How to check weak SSL ciphers? ›
How to do it...
- Open the terminal and launch the SSLScan tool, as shown in the following screenshot:
- To scan your target using SSLScan, run the following command: sslscan demo.testfire.net.
- SSLScan will test the SSL certificate for the all the ciphers it supports. Weak ciphers will be shown in red and yellow.
Disable specific ciphers and protocols- Version 16.2 (Build 37799) and above
- In a text editor, open the following file: ...
- Locate the two lines starting with “#server.ssl.disabled-protocols” and “#server.ssl.disabled-cipher-suites”
- Remove the proceeding # sign to uncomment the lines and edit the list as needed.
The use of strong ciphers is critical to maintaining strong encryption on your web server, load balancer, or proxy. Weak ciphers may compromise the security of your site or your users by allowing legacy user agents to connect to your site in a vulnerable way.
How do I disable weak SSL ciphers in Windows? ›
You can do this using GPO or Local security policy under Computer configuration > Administrative Templates > Network > SSL Configuration Settings > SSL Cipher Suite Order. Set this policy to enable. Each cipher suite should be separated with a comma. Remove as needed based on the list below.
5 answers
- Click Start, click Run, type regedit in the Open box, and then click OK.
- Locate and then click the following subkey: *HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\KeyExchangeAlgorithms*
- On the Edit menu, point to New, and then click Key.
Although an SSL certificate means that your connection to a website is secure, it doesn't necessarily mean that the website is safe to use. For example, malicious websites can also obtain some types of SSL certificates, such as DV certificates.
How do I know if a website is SSL secure? ›
How do I view an SSL certificate in Chrome or Firefox?
- Select the padlock icon located in the address bar of the website.
- In the pop-up window, choose "Certificate (Valid)."
- Review the "Valid from" dates to ensure the SSL certificate is up-to-date.
Find the cipher using Chrome
- Launch Chrome.
- Enter the URL you wish to check in the browser.
- Click on the ellipsis located on the top-right in the browser.
- Select More tools > Developer tools > Security.
- Look for the line "Connection...". This will describe the version of TLS or SSL used.
What weak and insecure SSL ciphers are detected by Alert Logic scans?
| ADH-AES128-GCM-SHA256 | DHE-PSK-AES256-CBC-SHA |
|---|
| AECDH-RC4-SHA | ECDH-RSA-NULL-SHA |
| AES128-SHA | ECDH-RSA-RC4-SHA |
| AES256-SHA | ECDHE-ECDSA-AES128-SHA |
| CAMELLIA128-SHA | ECDHE-ECDSA-AES256-SHA |
42 more rowsA cipher suite is identified as obsolete when one or more of the mechanisms is weak. Especially weak encryption algorithms in TLS 1.2 are designated as NULL, RC2, RC4, DES, IDEA, and TDES/3DES; cipher suites using these algorithms should not be used9.
Is weak encryption a threat? ›
Vulnerabilities in Weak Encryption Keys
Weaknesses in how encryption keys are generated can also create vulnerabilities. For example, keys generated by simple mathematical functions instead of secure random number generation make it possible for attackers to more easily guess the keys through cryptanalysis.
What is the vulnerability of SSL? ›
Heartbleed bug is a vulnerability in the OpenSSL, a popular open source cryptographic library that helps in the implementation of SSL and TLS protocols. This bug allows attackers to steal private keys attached to SSL certificates, usernames, passwords and other sensitive data without leaving a trace.
What is the impact of not using SSL? ›
Without an SSL certificate, your website is vulnerable to security threats and potential data breaches. Without the secure connection provided by SSL, sensitive information such as passwords, credit card details, and personal data transmitted through your site can be intercepted by cybercriminals.
What are the risks of SSL inspection? ›
Issues with decrypted traffic: Since the SSL inspection process must decrypt SSL traffic, this creates a window that attackers can exploit to steal data, plant malicious content, or affect the data flow.
