Kerio MailServer IMAP Server Crafted LOGIN Command DoS

high Nessus Plugin ID 21050
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The remote IMAP server is prone to denial of service attacks.


The remote host is running Kerio MailServer, a commercial mail server available for Windows, Linux, and Mac OS X platforms.

The installed version of Kerio MailServer terminates abnormally when it receives certain malformed IMAP LOGIN commands. An unauthenticated, remote attacker can exploit this issue to deny access to legitimate users.

Note that the application may not terminate immediately but only after an administrator acknowledges a console message.


Upgrade to Kerio MailServer 6.1.3 Patch 1 or later.

See Also

Plugin Details

Severity: High

ID: 21050

File Name: kerio_kms_imap_login_dos.nasl

Version: 1.21

Type: remote

Published: 3/13/2006

Updated: 11/15/2018

Dependencies: find_service1.nasl, imap_overflow.nasl

Risk Information


Risk Factor: Low

Score: 3.4


Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:2.3:a:kerio:kerio_mailserver:*:*:*:*:*:*:*:*

Excluded KB Items: imap/false_imap, imap/overflow

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 3/9/2006

Reference Information

CVE: CVE-2006-1158

BID: 17043