CVE-2020-3132: A vulnerability in the email message scanning feature of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticate...

Description

A vulnerability in the email message scanning feature of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a temporary denial of service (DoS) condition on an affected device. The vulnerability is due to inadequate parsing mechanisms for specific email body components. An attacker could exploit this vulnerability by sending a malicious email containing a high number of shortened URLs through an affected device. A successful exploit could allow the attacker to consume processing resources, causing a DoS condition on an affected device. To successfully exploit this vulnerability, certain conditions beyond the control of the attacker must occur.

Metrics

CVSS 3.1

5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.47%

70.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Cloud Email Security	< 12.5.1-037
Cisco	Email Security Appliance	< 12.5.1-037
Cisco	Cloud Email Security	< 13.0.0-375
Cisco	Email Security Appliance	< 13.0.0-375

References

Timeline

Published: Feb 19, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-3132?

A vulnerability in the email message scanning feature of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a temporary denial of service (DoS) condition on an affected device. The vulnerability is due to inadequate parsing mechanisms for specific email body components. An attacker could exploit this vulnerability by sending a malicious email containing a high number of shortened URLs through an affected device. A successful exploit could allow the attacker to consume processing resources, causing a DoS condition on an affected device. To successfully exploit this vulnerability, certain conditions beyond the control of the attacker must occur.

How severe is CVE-2020-3132?

CVE-2020-3132 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 1.47% probability of exploitation in the next 30 days.

How do I fix CVE-2020-3132?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.