CVE-2018-15453 Information

Description

A vulnerability in the Secure/Multipurpose Internet Mail Extensions (S/MIME) Decryption and Verification or S/MIME Public Key Harvesting features of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated remote attacker to cause an affected device to corrupt system memory. A successful exploit could cause the filtering process to unexpectedly reload resulting in a denial of service (DoS) condition on the device. The vulnerability is due to improper input validation of S/MIME-signed emails. An attacker could exploit this vulnerability by sending a malicious S/MIME-signed email through a targeted device. If Decryption and Verification or Public Key Harvesting is configured the filtering process could crash due to memory corruption and restart resulting in a DoS condition. The software could then resume processing the same S/MIME-signed email causing the filtering process to crash and restart again. A successful exploit could allow the attacker to cause a permanent DoS condition. This vulnerability may require manual intervention to recover the ESA.

CVSS Vector

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

Reference

http://www.securityfocus.com/bid/106511 https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190109-esa-dos

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

CHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

8.6