CVE Vulnerabilities

CVE-2021-20237

Uncontrolled Resource Consumption

Published: May 28, 2021 | Modified: Nov 21, 2024
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
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
5.9 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Ubuntu
LOW

An uncontrolled resource consumption (memory leak) flaw was found in ZeroMQs src/xpub.cpp in versions before 4.3.3. This flaw allows a remote unauthenticated attacker to send crafted PUB messages that consume excessive memory if the CURVE/ZAP authentication is disabled on the server, causing a denial of service. The highest threat from this vulnerability is to system availability.

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

Name Vendor Start Version End Version
Libzmq Zeromq 4.2.0 (including) 4.3.3 (excluding)
Zeromq3 Ubuntu bionic *
Zeromq3 Ubuntu esm-apps/bionic *
Zeromq3 Ubuntu esm-apps/focal *
Zeromq3 Ubuntu focal *
Zeromq3 Ubuntu groovy *
Zeromq3 Ubuntu trusty *
Zeromq3 Ubuntu upstream *
Zeromq3 Ubuntu xenial *

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