KPMG-2002004: Lotus Domino Webserver DOS-device Denial of Service

Type securityvulns
Reporter Securityvulns
Modified 2002-02-05T00:00:00


  -=>Lotus Domino Webserver DOS-device Denial of Service<=-
                  courtesy of KMPG Denmark

BUG-ID: 2002004 Released: 4th Feb 2002


The Domino Webserver does not handle URL request for DoS-Devices correctly. This vulnerability can be exploited by a malicious user to bring down the webserver.


  • Lotus Domino Webserver prior to 5.0.9a on Windows 2000


there are two issues in the Domino Webserver that give similar results when exploited.

First issue) A request for a DOS-device from CGI-BIN with any given extension is accepted by the server as a valid request and is passed on the to cgihandler (nhttpcgi.exe). Due to the nature of DOS- devices (CON, AUX, PRN etc.) the process never releases the file again, and when Domino's limit of 400 working threads has been reached, the server will no longer accept requests.

Second issue) Requesting a DOS-device (eg. NUL) from CGI-BIN with an extension of 220 chars (eg. 220x"a") results in the server spawning cmd.exe to run, in this case, nul.pif. The server will then pop up a window, asking which file you want to open nul.pif with. This can be done 400 times, before the server runs out of working threads or less, if it runs out of memory, since this attack opens up a lot of processes.

Vendor URL:

You can visit the vendors webpage here:

Vendor response:

The vendor was contacted on the 1st of November, 2001. On the 5th of November the vendor confirms that they have reproduced the issues on Windows 2000. The issues were assigned bug id: JCHN4UMKLA and JCHN547JWV by the vendor. On the 4th of January, 2002, it was confirmed that the patch corrected the two issues mentioned in this advisory.

Corrective action:

Upgrade to Domino 5.0.9a, which can be downloaded here:

Author: Peter Grьndl (

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