Sendmail < 8.14.4 SSL Certificate NULL Character Spoofing

high Nessus Plugin ID 43637
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The remote mail server is susceptible to a man-in-the-middle attack.


The remote mail server is running a version of Sendmail earlier than 8.14.4. Such versions are reportedly affected by a flaw that may allow an attacker to spoof SSL certificates by using a NULL character in certain certificate fields.

A remote attacker may exploit this to perform a man-in-the-middle attack.


Upgrade to Sendmail 8.14.4 or later.

See Also

Plugin Details

Severity: High

ID: 43637

File Name: sendmail_8_14_4.nasl

Version: 1.20

Type: remote

Published: 1/5/2010

Updated: 9/17/2018

Dependencies: sendmail_detect.nbin

Risk Information

CVSS Score Source: CVE-2009-4565


Risk Factor: Low

Score: 3.4


Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

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


Risk Factor: High

Base Score: 7.3

Temporal Score: 6.4

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:sendmail:sendmail

Required KB Items: installed_sw/Sendmail

Exploit Ease: No known exploits are available

Patch Publication Date: 12/30/2009

Vulnerability Publication Date: 12/30/2009

Reference Information

CVE: CVE-2009-4565

BID: 37543

IAVA: 2010-A-0002

Secunia: 37998

CWE: 310