Lotus Notes R5 S/MIME Message Modification Warning Failure

Medium Nessus Network Monitor Plugin ID 1304


The remote client does not properly flag tampered messages.


The remote host is running the Lotus Notes 5.x email client. Lotus Notes R5 client versions 5.0.5 and earlier could allow a remote attacker to send unsigned email messages as signed email messages, due to a vulnerability in the implementation of the S/MIME standard. Lotus Notes R5 client uses the S/MIME standard to securely send and receive messages with digital certificates. However, Lotus Notes fails to notify the recipient if the email being received has been tampered with. A remote attacker can corrupt signed messages in transit without the recipient being warned of the invalid signature. The message appears to the recipient as an unsigned message.


No known remedy as of August 2002 however at the time of writing Lotus Notes 6.0 is available.

Plugin Details

Severity: Medium

ID: 1304

File Name: 1304.prm

Family: SMTP Clients

Published: 2004/08/20

Modified: 2016/01/21

Dependencies: 1334

Risk Information

Risk Factor: Medium


Base Score: 4.3

Temporal Score: 3.6

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

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


Base Score: 5.3

Temporal Score: 4.9


Temporal Vector: CVSS3#E:F/RL:O/RC:C

Reference Information

CVE: CVE-2000-1138

BID: 1925