improve sequence

This commit is contained in:
Michael Jerger 2024-01-05 11:34:32 +01:00
parent fe9f26305f
commit b978642da0

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@ -1,4 +1,4 @@
# Threat analysis for the federated star activity
# Threat analysis for the federated Like Activity
See also [1] for getting an idea about the analysis.
@ -10,27 +10,25 @@ sequenceDiagram
participant fs as foreign_repository_server
participant os as our_repository_server
fs ->> os: post /api/activitypub/repository-id/1/inbox {Start-Activity}
fs ->> os: post /api/activitypub/repository-id/1/inbox {Like-Activity}
activate os
os ->> os: validate request inputs
os ->> repository: load 1
activate os
os ->> os: validate actor id inputs
os ->> fs: get .well-known/nodeinfo
os ->> NodeInfoWellKnown: create & validate
os ->> fs: get api/v1/nodeinfo
os ->> NodeInfo: create & validate
os ->> ForgeLike: validate
deactivate os
activate repository
os ->> repository: search for reop with object-id
deactivate repository
activate user
os ->> user: search for user with actor-id
user ->> user: create if not found
activate user
user ->> fs: get /api/activitypub/user-id/{id from actor}
user ->> user: validate response
user ->> user: create user from response
deactivate user
deactivate user
os ->> os: create user if not found
activate os
os ->> fs: get /api/activitypub/user-id/{id from actor}
os ->> ForgePerson: validate
os ->> user: create user from response
deactivate os
os ->> repository: execute star action
os -->> fs: 200 ok
deactivate os
@ -61,6 +59,7 @@ sequenceDiagram
{"id":"https://federated-repo.prod.meissa.de/api/v1/activitypub/user-id/10",
"type":"Person",
"preferredUsername":"stargoose9",
"name": "goose going to star the repo",
"publicKey":{"id":"https://federated-repo.prod.meissa.de/api/v1/activitypub/user-id/10#main-key",
"owner":"https://federated-repo.prod.meissa.de/api/v1/activitypub/user-id/10",
"publicKeyPem":"-----BEGIN PUBLIC KEY-----\nMIIBoj...XAgMBAAE=\n-----END PUBLIC KEY-----\n"}}
@ -94,12 +93,12 @@ flowchart TD
### Threat
1. Script Kiddi sends a Star Activity containing an attack actor url `http://attacked.target/very/special/path` in place of actor. Our repository server sends a `get Person Actor` request to this url. The target receives a DenialdOfService attack. We loose CPU & reputation.
2. Experienced hacker sends a Star Activity containing an actor url pointing to an evil forgejo instance. Our repository server sends an `get Person Actor` request to this instance and gets a person having sth. like `; drop database;` in its name. If our server tries to create a new user out of this persion, the db might be dropped.
1. Script Kiddi sends a Like Activity containing an attack actor url `http://attacked.target/very/special/path` in place of actor. Our repository server sends a `get Person Actor` request to this url. The target receives a DenialdOfService attack. We loose CPU & reputation.
2. Experienced hacker sends a Like Activity containing an actor url pointing to an evil forgejo instance. Our repository server sends an `get Person Actor` request to this instance and gets a person having sth. like `; drop database;` in its name. If our server tries to create a new user out of this persion, the db might be dropped.
3. OpenSource Promoter sends Star Activities containing non authorized Person Actors. The Actors listed as stargazer might get angry about this, we loose reputation.
4. Experienced Hacker records activities sent and replays some of them. Without order of activities (i.e. timestamp) we can not decide wether we should execute the activity again. If the replayed activities are Unstar Activity we might loose stars.
4. Experienced Hacker records activities sent and replays some of them. Without order of activities (i.e. timestamp) we can not decide wether we should execute the activity again. If the replayed activities are UnLike Activity we might loose stars.
5. Experienced Hacker records activities sends a massive amount of activities which leads to new user creation & storage loss. Our instance might fall out of service.
6. Experienced Hacker may craft their malicious server to keep connections open. Then they send a Star activity with the actor URL pointing to that malicious server, and your background job keeps waiting for data. Then they send more such requests, until you exhaust your limit of file descriptors openable for your system and cause a DoS (by causing cascading failures all over the system, given file descriptors are used for about everything, from files, to sockets, to pipes). See also [Slowloris@wikipedia][2].
6. Experienced Hacker may craft their malicious server to keep connections open. Then they send a Like Activity with the actor URL pointing to that malicious server, and your background job keeps waiting for data. Then they send more such requests, until you exhaust your limit of file descriptors openable for your system and cause a DoS (by causing cascading failures all over the system, given file descriptors are used for about everything, from files, to sockets, to pipes). See also [Slowloris@wikipedia][2].
### Mitigations
@ -133,5 +132,5 @@ In adition to direct commiter our special thanks goes to the experts joining our
## Reference
* [1]: https://geballte-sicherheit.de/threat-modelling-bedrohungsanalyse-7-teil-einstufung-von-bedrohungen-ranking-of-threats/
* [2]: https://en.wikipedia.org/wiki/Slowloris_(computer_security)
[1]: https://geballte-sicherheit.de/threat-modelling-bedrohungsanalyse-7-teil-einstufung-von-bedrohungen-ranking-of-threats/
[2]: https://en.wikipedia.org/wiki/Slowloris_(computer_security)