CVE-2020-3555 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SIP Denial of Service Vulnerability

Medium 6.8 Published Updated

Remote attackers can crash Cisco ASA and FTD devices by sending high-rate crafted SIP traffic, causing a denial of service.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
None listed

What is CVE-2020-3555?

CVE-2020-3555 is a medium-severity denial of service vulnerability in Cisco Adaptive Security Appliance, published on 21 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability in the SIP inspection process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a watchdog timeout and crash during the cleanup of threads that are associated with a SIP connection that is being deleted from the connection list. An attacker could exploit this vulnerability by sending a high rate of crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a watchdog timeout and crash, resulting in a crash and reload of the affected device.

Weakness: CWE-404

Which versions are affected by CVE-2020-3555?

It affects 3 products.

Products include Cisco Adaptive Security Appliance, Cisco Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense.

How do I fix CVE-2020-3555?

No fix has been published for CVE-2020-3555 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2020-3555 being exploited?

There is no known exploitation of CVE-2020-3555 in the wild and no public exploit code.

All Cisco Adaptive Security Appliance vulnerabilities

Sources

Also known as GHSA-r7x6-g4f2-fq99.

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