description: A vulnerability in Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated remote attacker to cause a denial of service (DoS) condition on an affected device.
This vulnerability is due to improper handling of certain TLS connections that are processed by an affected device. An attacker could exploit this vulnerability by establishing a large number of concurrent TLS connections to an affected device. A successful exploit could allow the attacker to cause the device to drop new TLS email messages that come from the associated email servers. Exploitation of this vulnerability does not cause the affected device to unexpectedly reload. The device will recover autonomously within a few hours of when the attack is halted or mitigated.
problem types: Uncontrolled Resource Consumption
affected:
{
vendor: Cisco
product: Cisco Secure Email
versions:
version: 11.0.3-238, status: affected
version: 11.1.0-069, status: affected
version: 11.1.0-131, status: affected
version: 11.1.0-128, status: affected
version: 12.0.0-419, status: affected
version: 12.1.0-071, status: affected
version: 12.1.0-087, status: affected
version: 12.1.0-089, status: affected
version: 13.0.0-392, status: affected
version: 13.5.1-277, status: affected
version: 12.5.0-066, status: affected
version: 14.0.0-698, status: affected
version: 14.2.0-620, status: affected
}
metrics:
format: cvssV3_1
cvssV3_1: [
version: 3.1
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
baseScore: 7.5
baseSeverity: HIGH
attackVector: NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: UNCHANGED
confidentialityImpact: NONE
integrityImpact: NONE
availabilityImpact: HIGH
]
exploits: The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.