GitHub Release: mastodon/mastodon v4.5.20 (29.10.2026)

Warning

While we do our best to support Mastodon 4.5 until 2027-02-20, there are known security issues in some of the dependencies we use.

We recommend administrators to update to a newer Mastodon version when they can, especially if you use OpenStack Swift for object storage.

Upgrade overview

This release contains upgrade notes that deviate from the norm:

ℹ️ Default Ruby version has been updated

For more information, view the complete release notes and scroll down to the upgrade instructions section.

Changelog

Security

• Fix insufficient ActivityPub identifier verification (GHSA-288h-6j8h-6x5j)


• Updated dependencies, in particular to address security advisories in Ruby, NodeJS, and sanitize

Fixed

• Fix inefficiency in some hashtag timeline queries (#41132 by @hugogameiro)


• Fix error in dev:populate_sample_data task (#40995 and #41051 by @isidzukuri and @mjankowski)

Upgrade notes

To get the code for v4.5.20, use git fetch && git checkout v4.5.20.

Note

As always, make sure you have backups of the database before performing any upgrades. If you are using docker-compose, this is how a backup command might look: docker exec mastodon_db_1 pg_dump -Fc -U postgres postgres > name_of_the_backup.dump

Dependencies

External dependencies have not changed since v4.5.0.

• Ruby: 3.2 or newer


• PostgreSQL: 14 or newer


• Elasticsearch (recommended, for full-text search): 7.x (OpenSearch should also work)


• LibreTranslate (optional, for translations): 1.3.3 or newer


• Redis: 7.0 or newer


• Node: 20.19 or newer


• libvips (optional, instead of ImageMagick): 8.13 or newer


• ImageMagick (optional if using libvips): 6.9.7-7 or newer

Update steps

The following instructions are for updating from 4.5.19.

If you are upgrading directly from an earlier release, please carefully read the upgrade notes for the skipped releases as well, as they often require extra steps such as database migrations. In particular, it is very important to read the 4.5.0 release notes.

Non-Docker

Tip

The charlock_holmes gem may fail to build on some systems with recent versions of gcc.

If you run into this issue, try BUNDLE_BUILD__CHARLOCK_HOLMES="--with-cxxflags=-std=c++17" bundle install.

1. If you are using rbenv, update the list of available versions and install the proper Ruby version by doing RUBY_CONFIGURE_OPTS=--with-jemalloc rbenv install in the Mastodon install directory (e.g. /home/mastodon/live)


2. Install dependencies with bundle install and yarn install --immutable


3. Restart all Mastodon processes.

When using Docker

1. Restart all Mastodon processes.