Coming early next year Drupal 6 will reach it's end of life and no longer be provided with code security updates or core commits.
According to Drupal.org:
- Drupal 6 will no longer be supported by the community at large. The community at large will no longer be creating new projects, fixing bugs in existing projects, writing documentation, etc. around Drupal 6.
- There will be no more core commits on Drupal 6.x to the official tree. (see What if I have a Drupal 6 site still)
- The security team will no longer provide support or Security Advisories for Drupal 6
- All Drupal 6 releases on project pages will be flagged as not supported.
- At some point in the future update status may stop working for Drupal 6 sites.
Read more at: https://www.drupal.org/drupal-6-eol