CVE-2018-0227

HIGH
7.5
CVSS Score
Published: April 19, 2018 at 08:00 PM UTC
Updated: August 11, 2026 at 07:37 PM UTC
2 products affected across 1 vendorAdaptive Security ApplianceSecure Firewall Threat Defense

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Severity
HIGH7.5
Exploit prediction
EPSS 2%
SSVC
No known exploit

Description

A vulnerability in the Secure Sockets Layer (SSL) Virtual Private Network (VPN) Client Certificate Authentication feature for Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to establish an SSL VPN connection and bypass certain SSL certificate verification steps. The vulnerability is due to incorrect verification of the SSL Client Certificate. An attacker could exploit this vulnerability by connecting to the ASA VPN without a proper private key and certificate pair. A successful exploit could allow the attacker to establish an SSL VPN connection to the ASA when the connection should have been rejected. This vulnerability affects Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) Software that is running on the following Cisco products: 3000 Series Industrial Security Appliances (ISA), ASA 5500 Series Adaptive Security Appliances, ASA 5500-X Series Next-Generation Firewalls, ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Adaptive Security Virtual Appliances (ASAv), Firepower 4110 Security Appliances, Firepower 9300 ASA Security Modules. Cisco Bug IDs: CSCvg40155.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

9.4.4 ≤ v ≤ 9.4.4.139.5.3.7 ≤ v ≤ 9.5.3.99.6.2.9 ≤ v ≤ 9.6.2.219.6.3 ≤ v ≤ 9.6.3.179.4.3.19.4.3.29.5.2.79.5.2.8
6.0 ≤ v ≤ 6.0.1.46.1.0 ≤ v ≤ 6.1.0.5

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

VDB Entryx_refsource_BIDThird Party Advisory
http://www.securityfocus.com/bid/104018
VDB Entryx_refsource_SECTRACKThird Party Advisory
http://www.securitytracker.com/id/1040723
x_refsource_MISCThird Party AdvisoryUS Government Resource
https://ics-cert.us-cert.gov/advisories/ICSA-18-184-01

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-295

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