CVE-2017-6441 Explained : Impact and Mitigation
Learn about CVE-2017-6441 in PHP 7.1.2 where attackers can exploit _zval_get_long_func_ex to trigger a denial of service attack. Understand the impact, affected systems, and mitigation steps.
In PHP 7.1.2, a function called _zval_get_long_func_ex can be exploited to trigger a denial of service attack. The vendor disputes this as a vulnerability.
Understanding CVE-2017-6441
In PHP 7.1.2, the _zval_get_long_func_ex function in Zend/zend_operators.c can be manipulated to cause a denial of service attack.
What is CVE-2017-6441?
The _zval_get_long_func_ex function in PHP 7.1.2 can be abused to trigger a denial of service attack by manipulating the "declare(ticks=" statement in a PHP script.
The Impact of CVE-2017-6441
Exploiting this vulnerability can lead to a NULL pointer dereference and subsequent application crash, resulting in a denial of service.
Technical Details of CVE-2017-6441
In-depth technical information about the vulnerability.
Vulnerability Description
The _zval_get_long_func_ex function in PHP 7.1.2 allows attackers to cause a denial of service through crafted use of "declare(ticks=" in a PHP script.
Affected Systems and Versions
- Affected Version: PHP 7.1.2
- Vendor: PHP
Exploitation Mechanism
Attackers exploit the _zval_get_long_func_ex function by manipulating the "declare(ticks=" statement in a PHP script.
Mitigation and Prevention
Measures to address and prevent the CVE-2017-6441 vulnerability.
Immediate Steps to Take
- Monitor vendor updates and patches
- Implement code review processes to detect and mitigate vulnerabilities
Long-Term Security Practices
- Regularly update PHP to the latest version
- Follow secure coding practices to minimize the risk of exploitation
Patching and Updates
Stay informed about patches and updates released by PHP to address the vulnerability.