Wire-server is the system server for the wire back-end services. Releases prior to v2022-03-01 are subject to a denial of service attack via a crafted object causing a hash collision. This collision causes the server to spend at least quadratic time parsing it which can lead to a denial of service for a heavily used server. The issue has been fixed in wire-server 2022-03-01 and is already deployed on all Wire managed services. On premise instances of wire-server need to be updated to 2022-03-01, so that their backends are no longer affected. There are no known workarounds for this issue.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Wire-server | Wire | * | 2022-03-01 (excluding) |
| Haskell-aeson | Ubuntu | bionic | * |
| Haskell-aeson | Ubuntu | esm-apps/bionic | * |
| Haskell-aeson | Ubuntu | esm-apps/focal | * |
| Haskell-aeson | Ubuntu | esm-apps/jammy | * |
| Haskell-aeson | Ubuntu | esm-apps/xenial | * |
| Haskell-aeson | Ubuntu | focal | * |
| Haskell-aeson | Ubuntu | impish | * |
| Haskell-aeson | Ubuntu | jammy | * |
| Haskell-aeson | Ubuntu | kinetic | * |
| Haskell-aeson | Ubuntu | trusty | * |
| Haskell-aeson | Ubuntu | upstream | * |
| Haskell-aeson | Ubuntu | xenial | * |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.