A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting the URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

A vulnerability in the MP3 detection engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper validation of certain MP3 file types. An attacker could exploit this vulnerability by sending a crafted MP3 file through the targeted device. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.

A vulnerability in the Sender Policy Framework (SPF) functionality of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the configured user filters on an affected device. The vulnerability exists because the affected software insufficiently validates certain incoming SPF messages. An attacker could exploit this vulnerability by sending a custom SPF packet to an affected device. A successful exploit could allow the attacker to bypass the configured header filters, which could allow malicious content to pass through the device.

Cross-site scripting (XSS) vulnerability in Cisco AsyncOS on the Web Security Appliance (WSA) 9.0.0-193; Email Security Appliance (ESA) 8.5.6-113, 9.1.0-032, 9.1.1-000, and 9.6.0-000; and Content Security Management Appliance (SMA) 9.1.0-033 allows remote attackers to inject arbitrary web script or HTML via an unspecified parameter, aka Bug IDs CSCuu37430, CSCuu37420, CSCut71981, and CSCuv50167.