CVE Vulnerabilities

CVE-2021-41119

Uncontrolled Resource Consumption

Published: Apr 13, 2022 | Modified: Apr 21, 2022
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM

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.

Weakness

The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.

Affected Software

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 *

Extended Description

Limited resources include memory, file system storage, database connection pool entries, and CPU. If an attacker can trigger the allocation of these limited resources, but the number or size of the resources is not controlled, then the attacker could cause a denial of service that consumes all available resources. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system. There are at least three distinct scenarios which can commonly lead to resource exhaustion:

Resource exhaustion problems are often result due to an incorrect implementation of the following situations:

Potential Mitigations

  • 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.

References