CVE-2019-1947 Cisco Email Security Appliance Denial of Service Vulnerability

High 8.6 Published 23 Sep 2020 Updated 13 Nov 2024

Unauthenticated remote attackers can cause permanent denial of service on Cisco Email Security Appliances by sending emails with large attachments.

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-2019-1947?

CVE-2019-1947 is a high-severity denial of service vulnerability in Cisco Asyncos, published on 23 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause the CPU utilization to increase to 100 percent, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of email messages that contain large attachments. An attacker could exploit this vulnerability by sending a malicious email message through the targeted device. A successful exploit could allow the attacker to cause a permanent DoS condition due to high CPU utilization. This vulnerability may require manual intervention to recover the ESA.

Weakness: CWE-20

Which versions are affected by CVE-2019-1947?

It affects 2 products.

Products include Cisco Asyncos, Cisco Email Security Appliance.

How do I fix CVE-2019-1947?

No fix has been published for CVE-2019-1947 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-2019-1947 being exploited?

There is no known exploitation of CVE-2019-1947 in the wild and no public exploit code.

All Cisco Asyncos vulnerabilities

Sources

Also known as GHSA-57m9-xcr9-qv37.