CVE-2020-3574: Cisco IP Phone TCP Packet Flood Denial of Service Vulnerability

Published Nov 6, 2020
·
Updated

A vulnerability in the TCP packet processing functionality of Cisco IP Phones could allow an unauthenticated, remote attacker to cause the phone to stop responding to incoming calls, drop connected calls, or unexpectedly reload. The vulnerability is due to insufficient TCP ingress packet rate limiting. An attacker could exploit this vulnerability by sending a high and sustained rate of crafted TCP traffic to the targeted device. A successful exploit could allow the attacker to impact operations of the phone or cause the phone to reload, leading to a denial of service (DoS) condition.

Affected Software

16 affected components
Cisco Ip Dect 210 Firmware<4.8.1
Cisco Ip Dect 210
Cisco Ip Dect 6825 Firmware<4.8.1
Cisco Ip Dect 6825
Cisco Ip Phone 8811 Firmware<11.3.2
Cisco Ip Phone 8811
Cisco Ip Phone 8841 Firmware<11.3.2
Cisco Ip Phone 8841
Cisco Ip Phone 8851 Firmware<11.3.2
Cisco IP Phone 8851
Cisco Ip Phone 8861 Firmware<11.3.2
Cisco Ip Phone 8861
Cisco Unified Ip Conference Phone 8831 Firmware=9.3\(4\)-servicerelease3
Cisco Unified Ip Conference Phone 8831
Cisco Webex Room Phone Firmware<1.2.0
Cisco Webex Room Phone

Event History

Nov 6, 2020
CVE Published
via MITRE·06:16 PM
Data Sourced
via MITRE·06:16 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2020-3574.

2

What is the severity of CVE-2020-3574?

The severity of CVE-2020-3574 is high with a severity value of 7.5.

3

What is the affected software?

The affected software includes Cisco IP Phones with firmware versions up to 4.8.1 and Cisco IP Phone models 8811, 8841, 8851, 8861 with firmware versions up to 11.3.2.

4

How does the vulnerability affect Cisco IP Phones?

The vulnerability could allow an unauthenticated, remote attacker to cause the phone to stop responding to incoming calls, drop connected calls, or unexpectedly reload.

5

How can I fix CVE-2020-3574?

To fix CVE-2020-3574, Cisco recommends updating the firmware of the affected IP Phones to a version that addresses the vulnerability.

Contact

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