The proxy server in Kerio WinRoute Firewall before 6.4.1 does not properly enforce authentication for HTTPS pages, which has unknown impact and attack vectors. NOTE: it is not clear whether this issue crosses privilege boundaries.

Kerio WinRoute Firewall 6.2.2 and earlier allows remote attackers to cause a denial of service (crash) via malformed DNS responses.

Kerio WinRoute Firewall before 6.2.1 allows remote attackers to cause a denial of service (application crash) via unknown vectors in the "email protocol inspectors," possibly (1) SMTP and (2) POP3.

Multiple unspecified vulnerabilities in Kerio WinRoute Firewall before 6.1.4 Patch 1 allow remote attackers to cause a denial of service via multiple unspecified vectors involving (1) long strings received from Active Directory and (2) the filtering of HTML.

Kerio WinRoute Firewall before 6.1.4 Patch 2 allows attackers to cause a denial of service (CPU consumption and hang) via unknown vectors involving "browsing the web".

Unspecified vulnerability in Kerio WinRoute Firewall before 6.1.3 allows remote attackers to cause a denial of service (crash) via certain RTSP streams.

The administration protocol for Kerio WinRoute Firewall 6.x up to 6.0.10, Personal Firewall 4.x up to 4.1.2, and MailServer up to 6.0.8 allows remote attackers to quickly obtain passwords that are 5 characters or less via brute force methods.

The administration protocol for Kerio WinRoute Firewall 6.x up to 6.0.10, Personal Firewall 4.x up to 4.1.2, and MailServer up to 6.0.8 allows remote attackers to cause a denial of service (CPU consumption) via certain attacks that force the product to "compute unexpected conditions" and "perform cryptographic operations."

Kerio Winroute Firewall before 6.0.9, ServerFirewall before 1.0.1, and MailServer before 6.0.5, when installed on Windows based systems, do not modify the ACLs for critical files, which allows local users with Power Users privileges to modify programs, install malicious DLLs in the plug-ins folder, and modify XML files related to configuration.

Kerio Winroute Firewall before 6.0.7, ServerFirewall before 1.0.1, and MailServer before 6.0.5 use symmetric encryption for user passwords, which allows attackers to decrypt the user database and obtain the passwords by extracting the secret key from within the software.