SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-34741

A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device.

HIGH 7.5EPSS 1.29%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.29% probability · 69th percentile
CISA KEV
Not listed
Weakness
CWE-770
Affected
cisco/asyncos
Source
psirt@cisco.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.