Heroku-22 and Heroku-24 stacks updated

Change effective on 08 September 2025

We updated the heroku-22 and heroku-24 stacks to pick up security fixes in upstream packages. The new base images for each stack roll out automatically to the Common Runtime over the next 48 hours, followed by Private Spaces.

If you use Heroku’s default buildpack-powered build system/stacks, you don’t need to redeploy your app to include these changes. We automatically restart any running dynos as we roll out the new base images for each stack. For Cedar-generation apps, each time a dyno starts, the slug applies on top of the most recent base image. For Fir-generation apps, the built image gets rebased on top of the most recent base image.

If your app uses Heroku’s container stack (most don’t), you must rebuild your app’s Docker image to pick up updates in the base image specified in your Dockerfile.

See this Dev Center article for an overview of the packages available in each stack’s base image.

Changelog of packages

Stack: heroku-22

  • Updated linux-libc-dev from version 5.15.0-152.162 to 5.15.0-153.163

Updates to packages available at build time only

  • Added python3-tomli version 1.2.2-2

Stack: heroku-24

  • Added media-types version 10.1.0

Updates to packages available at build time only

  • Updated linux-libc-dev from version 6.8.0-78.78 to 6.8.0-79.79