For those who simply need to know the worst offenders linked to version "5640," here are the top CVEs that remain unpatched in 5.6.40.
An issue in the _gdContributionsAlloc function in gd_interpolation.c can have unspecified impacts via unauthenticated remote attacks.
Vulnerabilities in PHP 5.6.40 can allow attackers to execute arbitrary code on your server, leading to total server compromise. php version 5640 vulnerabilities link
For a long time, Old Faithful felt secure. After all, 5.6.40 was a "security release." It had been patched to fix multiple vulnerabilities that plagued earlier 5.6.x versions, including integer underflow, buffer overflows, and out-of-bounds read errors . It was the fortress built to withstand the dying days of an era.
Some notable CVEs that affect 5.6.40:
The core issues found in PHP 5.6.40 typically reside within its built-in extensions—specifically standard data handling tools like Multibyte String ( mbstring ), the GD Graphics Library , XML-RPC , and the PHAR stream wrapper. Because PHP 5 memory management lacks many modern guardrails found in PHP 8.x, attackers exploit these extensions to corrupt memory and force system level actions.
Running PHP 5.6.40 means your application is exposed to numerous publicly known vulnerabilities that will never be patched by the PHP Group. As indicated by Influential Software , running unsupported software is not a viable strategy for any organization concerned with data integrity. Key Security Vulnerabilities For those who simply need to know the
For a complete list of vulnerabilities, you can check the PHP changelog or the National Vulnerability Database (NVD).
There is no single “master link” labeled "5640." Instead, you must look at the aggregate of Common Vulnerabilities and Exposures (CVEs) that affect version 5.6.40. For a long time, Old Faithful felt secure