CVE-2019-9641 Explained : Impact and Mitigation

A vulnerability has been found in the EXIF module in PHP versions prior to 7.1.27, 7.2.x prior to 7.2.16, and 7.3.x prior to 7.3.3. The issue involves an uninitialized reading operation in the exif_process_IFD_in_TIFF function.

Understanding CVE-2019-9641

This CVE entry describes a vulnerability in PHP versions prior to 7.1.27, 7.2.x prior to 7.2.16, and 7.3.x prior to 7.3.3 related to the EXIF module.

What is CVE-2019-9641?

CVE-2019-9641 is a security vulnerability found in the EXIF component of PHP versions before 7.1.27, 7.2.x before 7.2.16, and 7.3.x before 7.3.3. The vulnerability is due to an uninitialized read operation in the exif_process_IFD_in_TIFF function.

The Impact of CVE-2019-9641

This vulnerability could allow an attacker to execute arbitrary code or cause a denial of service by exploiting the uninitialized read operation in the EXIF component of PHP.

Technical Details of CVE-2019-9641

This section provides more technical details about the CVE.

Vulnerability Description

The vulnerability involves an uninitialized read operation in the exif_process_IFD_in_TIFF function within the EXIF component of PHP.

Affected Systems and Versions

PHP versions prior to 7.1.27
PHP 7.2.x versions prior to 7.2.16
PHP 7.3.x versions prior to 7.3.3

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting a malicious EXIF image that triggers the uninitialized read operation, potentially leading to arbitrary code execution or denial of service.

Mitigation and Prevention

Protecting systems from CVE-2019-9641 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update PHP to versions 7.1.27, 7.2.16, or 7.3.3 or later to mitigate the vulnerability.
Monitor for any unusual activities that could indicate exploitation of the vulnerability.

Long-Term Security Practices

Regularly update PHP and other software components to the latest versions to address known security issues.
Implement proper input validation and sanitization to prevent malicious inputs from exploiting vulnerabilities.

Patching and Updates

Apply patches provided by PHP to fix the uninitialized read vulnerability in the EXIF component.