CVE-2018-15453

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.

• CVE ID
• CVE-2018-15453

• Assigner
• ykramarz@cisco.com

• Vulnerability Status
• Analyzed

• Published Version
• 2019-01-10T18:29:00

• Last Modified Date
• 2020-09-16T14:13:44

• Version
• 2.0

• Vector String
• AV:N/AC:L/Au:N/C:N/I:N/A:C

• Access Vector
• NETWORK

• Access Compatibility
• LOW

• Authentication
• NONE

• Confidentiality Impact
• NONE

• Integrity Impact
• NONE

• Availability Impact
• COMPLETE

• Base Score
• 7.8

• Severity
• HIGH

• Exploitability Score
• 10

• Impact Score
• 6.9

• Version
• 3.1

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

• Attack Vector
• NETWORK

• Attack Compatibility
• LOW

• Privileges Required
• NONE

• User Interaction
• NONE

• Scope
• CHANGED

• Confidentiality Impact
• NONE

• Availability Impact
• HIGH

• Base Score
• 8.6

• Base Severity
• HIGH

• Exploitability Score
• 3.9

• Impact Score
• 4