Backporting

The porting of a code snippet, module, or other part of a program to an older version of the software. In the field of information security, backporting refers to an attempt to install a patch for a vulnerability in the current build of an application on top of an earlier version. This is required when a vendor releases a security update only for the current release of an application (for example, when the outdated version is no longer supported). Backporting is most often performed by third-party developers and information security enthusiasts.