0c2b33458d
In Mastodon media can only be used by owners and only be associated with
a single post. We currently allow media to be associated with several
posts and until now did not limit their usage in posts to media owners.
However, media update and GET lookup was already limited to owners.
(In accordance with allowing media reuse, we also still allow GET
lookups of media already used in a post unlike Mastodon)
Allowing reuse isn’t problematic per se, but allowing use by non-owners
can be problematic if media ids of private-scoped posts can be guessed
since creating a new post with this media id will reveal the uploaded
file content and alt text.
Given media ids are currently just part of a sequentieal series shared
with some other objects, guessing media ids is with some persistence
indeed feasible.
E.g. sampline some public media ids from a real-world
instance with 112 total and 61 monthly-active users:
17.465.096 at t0
17.472.673 at t1 = t0 + 4h
17.473.248 at t2 = t1 + 20min
This gives about 30 new ids per minute of which most won't be
local media but remote and local posts, poll answers etc.
Assuming the default ratelimit of 15 post actions per 10s, scraping all
media for the 4h interval takes about 84 minutes and scraping the 20min
range mere 6.3 minutes. (Until the preceding commit, post updates were
not rate limited at all, allowing even faster scraping.)
If an attacker can infer (e.g. via reply to a follower-only post not
accessbile to the attacker) some sensitive information was uploaded
during a specific time interval and has some pointers regarding the
nature of the information, identifying the specific upload out of all
scraped media for this timerange is not impossible.
Thus restrict media usage to owners.
Checking ownership just in ActivitDraft would already be sufficient,
since when a scheduled status actually gets posted it goes through
ActivityDraft again, but would erroneously return a success status
when scheduling an illegal post.
Independently discovered and fixed by mint in Pleroma
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| .woodpecker | ||
| benchmarks | ||
| ci | ||
| config | ||
| docker-resources | ||
| docs | ||
| installation | ||
| lib | ||
| priv | ||
| rel | ||
| restarter | ||
| scripts | ||
| test | ||
| uploads | ||
| .credo.exs | ||
| .dockerignore | ||
| .formatter.exs | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| AGPL-3 | ||
| CC-BY-4.0 | ||
| CC-BY-SA-4.0 | ||
| CHANGELOG.md | ||
| CODE_OF_CONDUCT.md | ||
| COPYING | ||
| docker-compose.yml | ||
| docker-entrypoint.sh | ||
| Dockerfile | ||
| mix.exs | ||
| mix.lock | ||
| README.md | ||
| SECURITY.md | ||
| SIGNING_KEY.pub | ||
akkoma
a smallish microblogging platform, aka the cooler pleroma
About
This is a fork of Pleroma, which is a microblogging server software that can federate (= exchange messages with) other servers that support ActivityPub. What that means is that you can host a server for yourself or your friends and stay in control of your online identity, but still exchange messages with people on larger servers. Akkoma will federate with all servers that implement ActivityPub, like Friendica, GNU Social, Hubzilla, Mastodon, Misskey, Peertube, and Pixelfed.
Akkoma is written in Elixir and uses PostgreSQL for data storage.
For clients it supports the Mastodon client API with Pleroma extensions (see the API section on https://docs.akkoma.dev/stable/).
Differences with Pleroma
Akkoma is a faster-paced fork, it has a varied and potentially experimental feature set tailored specifically to the corner of the fediverse inhabited by the project creator and contributors.
This should not be considered a one-for-one match with pleroma; it is more opinionated in many ways, and has a smaller community (which is good or bad depending on your view)
For example, Akkoma has:
- Custom Emoji reactions (compatible with misskey)
- Misskey-flavoured markdown support
- Elasticsearch and Meilisearch support for search
- Mastodon frontend (Glitch-Soc and Fedibird flavours) support
- Automatic post translation via DeepL or LibreTranslate
- A multitude of heavy modifications to the Pleroma Frontend (Pleroma-FE)
- The "bubble" concept, in which instance administrators can choose closely-related instances to make a "community of communities", so to say
And takes a more opinionated stance on issues like Domain blocks, which are enforced far more on Akkoma.
Take a look at the Changelog if you want a full list of recent changes, everything since 3.0 has been Akkoma.
Installation
OTP releases (Recommended)
If you are running Linux (glibc or musl) on x86, the recommended way to install Akkoma is by using OTP releases. OTP releases are as close as you can get to binary releases with Erlang/Elixir. The release is self-contained, and provides everything needed to boot it. The installation instructions are available here.
From Source
If your platform is not supported, or you just want to be able to edit the source code easily, you may install Akkoma from source.
Docker
Docker installation is supported via this setup
Packages
Akkoma is packaged for YunoHost and can be found and installed from the YunoHost app catalogue.
Compilation Troubleshooting
If you ever encounter compilation issues during the updating of Akkoma, you can try these commands and see if they fix things:
mix deps.clean --allmix local.rebarmix local.hexrm -r _build