CVE-2018-15388: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software WebVPN Denial of Service Vulnerability

Published May 3, 2019
·
Updated

A vulnerability in the WebVPN login process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause increased CPU utilization on an affected device. The vulnerability is due to excessive processing load for existing WebVPN login operations. An attacker could exploit this vulnerability by sending multiple WebVPN login requests to the device. A successful exploit could allow the attacker to increase CPU load on the device, resulting in a denial of service (DoS) condition.

Affected Software

34 affected components
Cisco Adaptive Security Appliance Software<9.4.4.34
Cisco Adaptive Security Appliance Software>=9.5<9.6.4.25
Cisco Adaptive Security Appliance Software>=9.7<9.8.4
Cisco Adaptive Security Appliance Software>=9.9<9.9.2.50
Cisco Asa 5505
Cisco Asa 5510
Cisco Asa 5512-x
Cisco Asa 5515-x
Cisco Asa 5520
Cisco Asa 5525-x
Cisco Asa 5540
Cisco Asa 5545-x
Cisco Asa 5550
Cisco Asa 5555-x
Cisco Asa 5580
Cisco Asa 5585-x
Cisco Firepower Threat Defense<6.2.3.12
All of the following
Any of the following
Cisco Adaptive Security Appliance Software<9.4.4.34
Cisco Adaptive Security Appliance Software>=9.5<9.6.4.25
Cisco Adaptive Security Appliance Software>=9.7<9.8.4
Cisco Adaptive Security Appliance Software>=9.9<9.9.2.50
Any of the following
Cisco Asa 5505
Cisco Asa 5510
Cisco Asa 5512-x
Cisco Asa 5515-x
Cisco Asa 5520
Cisco Asa 5525-x
Cisco Asa 5540
Cisco Asa 5545-x
Cisco Asa 5550
Cisco Asa 5555-x
Cisco Asa 5580
Cisco Asa 5585-x
Cisco Secure Firewall Threat Defense<6.2.3.12

Event History

May 3, 2019
CVE Published
via MITRE·02:30 PM
Data Sourced
via MITRE·02:30 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:29 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2018-15388?

CVE-2018-15388 is a vulnerability in the WebVPN login process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software.

2

How does CVE-2018-15388 impact the affected devices?

CVE-2018-15388 could allow an unauthenticated, remote attacker to cause increased CPU utilization on an affected device.

3

What is the severity of CVE-2018-15388?

CVE-2018-15388 has a severity rating of 8.6 (high).

4

How can I fix CVE-2018-15388?

There is currently no fixed software available for CVE-2018-15388. It is advised to follow the recommended mitigations provided by Cisco in their advisory.

5

Where can I find more information about CVE-2018-15388?

You can find more information about CVE-2018-15388 in the Cisco Security Advisory, which can be accessed at the following link: [Cisco Security Advisory - CVE-2018-15388](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190501-sd-cpu-dos)

Contact

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