CVE-2023-20177: Medium severity Cisco Secure Firewall Threat Defense vulnerability

Published Nov 1, 2023

Updated

A vulnerability in the SSL file policy implementation of Cisco Firepower Threat Defense (FTD) Software that occurs when the SSL/TLS connection is configured with a URL Category and the Snort 3 detection engine could allow an unauthenticated, remote attacker to cause the Snort 3 detection engine to unexpectedly restart. This vulnerability exists because a logic error occurs when a Snort 3 detection engine inspects an SSL/TLS connection that has either a URL Category configured on the SSL file policy or a URL Category configured on an access control policy with TLS server identity discovery enabled. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a crafted SSL/TLS connection through an affected device. A successful exploit could allow the attacker to trigger an unexpected reload of the Snort 3 detection engine, resulting in either a bypass or denial of service (DoS) condition, depending on device configuration. The Snort 3 detection engine will restart automatically. No manual intervention is required.

Affected Software

21 affected components

Cisco Secure Firewall Threat Defense=7.0.0

Cisco Secure Firewall Threat Defense=7.0.0.1

Cisco Secure Firewall Threat Defense=7.0.1

Cisco Secure Firewall Threat Defense=7.0.1.1

Cisco Secure Firewall Threat Defense=7.0.2

Cisco Secure Firewall Threat Defense=7.0.2.1

Cisco Secure Firewall Threat Defense=7.0.3

Cisco Secure Firewall Threat Defense=7.0.4

Cisco Secure Firewall Threat Defense=7.0.5

Cisco Secure Firewall Threat Defense=7.1.0

Cisco Secure Firewall Threat Defense=7.1.0.1

Cisco Secure Firewall Threat Defense=7.1.0.2

Cisco Secure Firewall Threat Defense=7.1.0.3

Cisco Secure Firewall Threat Defense=7.2.0

Cisco Secure Firewall Threat Defense=7.2.0.1

Cisco Secure Firewall Threat Defense=7.2.1

Cisco Secure Firewall Threat Defense=7.2.2

Cisco Secure Firewall Threat Defense=7.2.3

Cisco Secure Firewall Threat Defense=7.3.0

Cisco Secure Firewall Threat Defense=7.3.1

Cisco Secure Firewall Threat Defense=7.3.1.1

Event History

Nov 1, 2023

CVE Published

via MITRE·04:41 PM

Data Sourced

via MITRE·04:41 PM

DescriptionSeverityWeakness

Data Sourced

via NVD·05:15 PM

DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

What is the vulnerability ID of this security issue?

The vulnerability ID is CVE-2023-20177.

What is the affected software?

The affected software is Cisco Firepower Threat Defense version 7.0.0 to 7.3.1.1.

What is the severity of CVE-2023-20177?

The severity of CVE-2023-20177 is medium with a CVSS score of 4.

How can an attacker exploit this vulnerability?

An unauthenticated, remote attacker can exploit this vulnerability by causing the Snort 3 detection engine to utilize excessive memory when processing a malicious URL.

Is there a fix or patch available?

Yes, Cisco has released software updates to address this vulnerability. Please refer to the reference link for more information.