|Date: (C)2010-04-16 (M)2017-08-18|
|CVSS Score: 6.8||Access Vector: NETWORK|
|Exploitability Subscore: 8.6||Access Complexity: MEDIUM|
|Impact Subscore: 6.4||Authentication: NONE|
| ||Confidentiality: PARTIAL|
| ||Integrity: PARTIAL|
| ||Availability: PARTIAL|
Irssi before 0.8.15, when SSL is used, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) field or a Subject Alternative Name field of the X.509 certificate, which allows man-in-the-middle attackers to spoof IRC servers via an arbitrary certificate.