CVE-2020-3408: cisco cisco_ios Incorrect Regular Expression

Vulnerability summary

CVE-2020-3408 is a high (CVSS 8.6) Incorrect Regular Expression vulnerability in cisco cisco_ios. EPSS estimates a 1.55% chance of exploitation in the next 30 days, higher than 74.7% of scored vulnerabilities.

Timeline

1. 24-09-2020
   PublishedVulnerability first disclosed.
2. 13-11-2024
   Last modifiedVulnerability information updated.

Description

A vulnerability in the Split DNS feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability occurs because the regular expression (regex) engine that is used with the Split DNS feature of affected releases may time out when it processes the DNS name list configuration. An attacker could exploit this vulnerability by trying to resolve an address or hostname that the affected device handles. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

• CWE-185Incorrect Regular ExpressionThe product specifies a regular expression in a way that causes data to be improperly matched or compared.
• CWE-400Uncontrolled Resource ConsumptionThe product does not properly control the allocation and maintenance of a limited resource.