CVE-2020-7069 : Exploit Details and Defense Strategies

PHP versions 7.2.x below 7.2.34, 7.3.x below 7.3.23, and 7.4.x below 7.4.11 are affected by a vulnerability in AES-CCM encryption, potentially leading to decreased security and incorrect encryption data.

Understanding CVE-2020-7069

This CVE involves a flaw in the openssl_encrypt() function when used with AES-CCM mode and a 12-byte IV in specific PHP versions.

What is CVE-2020-7069?

In PHP versions 7.2.x below 7.2.34, 7.3.x below 7.3.23, and 7.4.x below 7.4.11, only the first 7 bytes of a 12-byte IV are utilized in AES-CCM mode encryption, potentially compromising security and data integrity.

The Impact of CVE-2020-7069

The vulnerability can result in reduced security levels and incorrect encryption of data due to the improper handling of IV bytes in AES-CCM encryption.

Technical Details of CVE-2020-7069

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

When AES-CCM mode is used with openssl_encrypt() function and a 12-byte IV in PHP versions mentioned, only the first 7 bytes of the IV are processed, leading to security and encryption issues.

Affected Systems and Versions

PHP 7.2.x versions below 7.2.34
PHP 7.3.x versions below 7.3.23
PHP 7.4.x versions below 7.4.11

Exploitation Mechanism

The vulnerability arises from the incorrect handling of IV bytes in AES-CCM encryption, allowing potential attackers to exploit this flaw to compromise data integrity.

Mitigation and Prevention

Protecting systems from CVE-2020-7069 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update PHP to versions 7.2.34, 7.3.23, or 7.4.11 to mitigate the vulnerability.
Monitor for any unusual activities that might indicate exploitation of the flaw.

Long-Term Security Practices

Regularly update PHP and other software components to stay protected against known vulnerabilities.
Implement secure coding practices to minimize the risk of similar issues in the future.

Patching and Updates

Apply patches provided by PHP Group to address the AES-CCM encryption vulnerability in affected versions.