Why are SSL/TLS certificates vulnerable?

Why are SSL/TLS certificates vulnerable?
SSL/TLS certificates are essential for website security but can be exploited if misconfigured. Common vulnerabilities include weak cipher suites, misconfigurations, and expired certificates. Attacks like BEAST, BREACH, and Heart-Bleed target SSL/TLS. Monitoring and updating certificates, using trusted authorities, and tools like Horizon can enhance security against SSL/TLS exploits.
Why are SSL/TLS certificates vulnerable?

Your SSL & TLS Certificates are Vulnerable

Having SSL/TLS certificates is vital for any organization, as they serve as digital certificates that verify the identity of a website and enable a secure connection between the client's browser and the server. However, if not properly configured, these certificates can be easily exploited byhackers to steal sensitive information.

It's worth noting that most organizations have an average of 23,000 certificate keys, and 54% of IT leaders are unaware of where they are stored. Attackers can launch Man-in-the-Middle attacks by exploiting vulnerabilities in SSL/TLS certificates, with DROWN and Heart-bleed being among the most common weaknesses.

Common Vulnerabilities in SSL/TLS Certificates

SSL/TLS certificates are critical to maintaining an organization's security, and their compromise can have severe consequences. Here are some common vulnerabilities to be aware of:

  1. Weak Cipher Suites: Encryption algorithms called cipher suites protect data in transit. Weak cipher suites can be compromised, leading to data confidentiality loss.
  2. Misconfigured Certificates: Proper configuration of certificates is crucial to ensure their security. Misconfigured certificates can leave systems vulnerable to various attacks that compromise data integrity and confidentiality.
  3. Certificate Authority Compromise: Certificate authorities (CAs) issue SSL/TLS certificates towebsites and organizations. If a CA is compromised, attackers can use fraudulent SSL/TLS certificates in man-in-the-middle attacks, causing significant harm to an organization's security.
  4. Heart-bleed Vulnerability: This vulnerability allows attackers to steal sensitive information, including SSL/TLS private keys, from vulnerable servers. With stolen information, attackers can engage in malicious activities like identity theft or financial fraud.
  5. Expired Certificates: SSL/TLS certificates have a validity period, and it is crucial to renew them before they expire. Failure to do so can render an organization vulnerable to attacks.

It is essential to safeguard SSL/TLS certificates to defend against attackers. Regular vulnerabilityassessments and security measures can help prevent SSL/TLS certificate exploits. Remember to monitor SSL/TLS certificate expiration dates and renew them promptly to ensure maximum security.

Common SSL Attacks

In the modern threat environment, malware is being designed specifically to exploit SSL/TLS keys and certificates. Take the Advanced Persistent Threat (APT) operators for instance. They exploited Heart-bleed malware to steal digital keys and certificates. This caused a data breach of 4.5 million Community Health System (CHS) patient records.

Some other common SSL attacks include:


The BEAST (Browser Exploit Against SSL/TLS) attack is a security vulnerability in the SSL/TLS protocol. This attack allows an attacker to intercept and decrypt encrypted session data. The BEAST attack is mitigated by using newer TLS versions, such as TLS v1.2 or TLS v1.3, or by using alternative cryptographic algorithms like ChaCha20-Poly1305 or AES-GCM.


The BREACH (Browser Reconnaissance and Exfiltration via Adaptive Compression of Hypertext) attack is a security vulnerability that affects web applications that use HTTP compression. This attack takes advantage of the fact that many web applications use compression algorithms to reduce the size of data being transmitted between the client and the server. By injecting specially crafted requests and analyzing the compressed response, attackers can infer the plaintext of encrypted data. This attack was used to compromise a PayPal account in 2013.

3. Heart-Bleed

Heart-Bleed is considered one of the most significant SSL/TLS vulnerabilities to date, impacting OpenSSL, a widely used open-source cryptographic library. The vulnerability allowed attackers to access sensitive information such as passwords and private keys from vulnerable web servers.


FREAK (Factoring RSA Export Keys) is an SSL/TLS attack that allows an attacker to force a website to use weak encryption, which can then be easily broken to reveal sensitive data. The vulnerability impacted many popular websites and services, including American Express and Dell.


The POODLE (Padding Oracle On Downgraded Legacy Encryption) attack forces web servers to downgrade protocol from TLS to SSLv3 by disturbing handshakes between the client and server. The attack allows hackers to steal sensitive data such as cookies or passwords from SSLv3-encrypted web traffic. This vulnerability impacted many popular websites and services, including Google, Facebook, and Yahoo.


The DROWN (Decrypting RSA with Obsolete and Weakened Encryption) attack allows attackers to decrypt intercepted traffic by reusing an SSLv2 server's RSA key exchange. This attack affected around a third of all HTTPS websites, including popular ones such as Yahoo and Alibaba.

It is crucial to ensure that SSL/TLS certificates are up-to-date to prevent similar vulnerabilities from being exploited. Here are some common ways to monitor SSL and TLS certificates.

Best practices to monitor SSL/TLS certificates

According to a survey conducted by Fortinet, managing SSL certificates is a significant challenge for major organizations. Unfortunately, many IT leaders and professionals in these organizations are unaware of how encryption keys are managed. However, there are several ways that organizations can protect themselves against cyberattacks related to SSL/TLS certificates.

One effective method is to maintain an up-to-date inventory of all SSL/TLS certificates used throughout the organization. This includes information such as the certificate authority and expiration date. Additionally, SSL/TLS certificates must be monitored regularly to ensure their configuration complies with industry standards. Setting up alerts to notify when a certificate is nearing its expiration date or has already expired is another way to keep track of SSL/TLS certificates.

Multi-factor authentication and other access controls are also crucial for securing SSL/TLS certificates and the systems that use them. In 2011, CA Comodo was hacked, which resulted in the issuance of fraudulent SSL/TLS certificates for popular sites such as Gmail, Microsoft Live, and Yahoo. To prevent such attacks, organizations should obtain SSL certificates from trusted certificate authorities.

Using an automated tool like an EASM platform can also help manage SSL/TLS certificates effectively. EASM can identify potential vulnerabilities in SSL/TLS certificates and alert security teams about possible threats. By following these measures, organizations can better protect themselves against cyberattacks related to SSI /TLS certificates.

Secure your organization against SSL/TLS exploits with Horizon

Keeping track of SSL/TLS certificates across your entire organization can be a daunting task, but Horizon provides a comprehensive solution to this problem.

With Horizon, you can confidently safeguard your organization's assets and protect against any potential threats. Horizon's asset discovery and monitoring features automatically scan for SSL/TLS certificate vulnerabilities and generate detailed reports with recommended actions, leaving no stone unturned. Moreover, Horizon's real-time monitoring capabilities use threat intelligence to proactively identify and prioritize vulnerabilities, keeping you one step ahead ofpotential threats.

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