CVE-2021-34787: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Identity-Based Rule Bypass Vulnerability

Published Oct 27, 2021
·
Updated

A vulnerability in the identity-based firewall (IDFW) rule processing feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass security protections. This vulnerability is due to improper handling of network requests by affected devices configured to use object group search. An attacker could exploit this vulnerability by sending a specially crafted network request to an affected device. A successful exploit could allow the attacker to bypass access control list (ACL) rules on the device, bypass security protections, and send network traffic to unauthorized hosts.

Affected Software

33 affected components
Cisco Adaptive Security Appliance<9.8.4.40
Cisco Firepower Threat Defense<6.4.0.13
Cisco Firepower Threat Defense>=6.5.0<6.6.5
Cisco Firepower Threat Defense>=6.7.0<6.7.0.3
Cisco Firepower Threat Defense>=7.0.0<7.0.1
Cisco Adaptive Security Appliance Software>=9.9.0<9.12.4.25
Cisco Adaptive Security Appliance Software>=9.13.0<9.14.3.1
Cisco Adaptive Security Appliance Software>=9.15.0<9.15.1.17
Cisco Adaptive Security Appliance Software>=9.16.0<9.16.1.28
Cisco Asa 5512-x Firmware=009.009
Cisco Asa 5512-x Firmware=009.012
Cisco Asa 5512-x
Cisco Asa 5505 Firmware=009.009
Cisco Asa 5505 Firmware=009.012
Cisco Asa 5505
Cisco Asa 5515-x Firmware=009.009
Cisco Asa 5515-x Firmware=009.012
Cisco Asa 5515-x
Cisco Asa 5525-x Firmware=009.009
Cisco Asa 5525-x Firmware=009.012
Cisco Asa 5525-x
Cisco Asa 5545-x Firmware=009.009
Cisco Asa 5545-x Firmware=009.012
Cisco Asa 5545-x
Cisco Asa 5555-x Firmware=009.009
Cisco Asa 5555-x Firmware=009.012
Cisco Asa 5555-x
Cisco Asa 5580 Firmware=009.009
Cisco Asa 5580 Firmware=009.012
Cisco Asa 5580
Cisco Asa 5585-x Firmware=009.009
Cisco Asa 5585-x Firmware=009.012
Cisco Asa 5585-x

Event History

Oct 27, 2021
CVE Published
via MITRE·06:56 PM
Data Sourced
via MITRE·06:56 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the vulnerability ID for this vulnerability?

The vulnerability ID for this vulnerability is CVE-2021-34787.

2

What is the affected software for this vulnerability?

The affected software for this vulnerability includes Cisco Adaptive Security Appliance (ASA) Software versions up to 9.8.4.40 and Cisco Firepower Threat Defense (FTD) Software versions up to 6.4.0.13.

3

What is the severity of CVE-2021-34787?

The severity of CVE-2021-34787 is medium with a CVSS score of 5.3.

4

How can an attacker exploit this vulnerability?

An unauthenticated, remote attacker can exploit this vulnerability to bypass security protections.

5

Is there a fix available for this vulnerability?

Yes, Cisco has released software updates to address this vulnerability. Please refer to the Cisco Security Advisory for more information and instructions on how to apply the patches.

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