CVE Vulnerabilities

CVE-2018-13805

Uncontrolled Resource Consumption

Published: Oct 10, 2018 | Modified: Mar 21, 2019
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.0/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

A vulnerability has been identified in SIMATIC ET 200SP Open Controller (All versions >= V2.0 and < V2.1.6), SIMATIC S7-1500 Software Controller (All versions >= V2.0 and < V2.5), SIMATIC S7-1500 incl. F (All versions >= V2.0 and < V2.5). An attacker can cause a denial-of-service condition on the network stack by sending a large number of specially crafted packets to the PLC. The PLC will lose its ability to communicate over the network. This vulnerability could be exploited by an attacker with network access to the affected systems. Successful exploitation requires no privileges and no user interaction. An attacker could use this vulnerability to compromise availability of the network connectivity. At the time of advisory publication no public exploitation of this vulnerability was known.

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
Simatic_et_200sp_firmware Siemens 2.0 *

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