Microsoft Exchange 2000 exhausts server resources while attempting to process malformed mail attributes

Overview

Microsoft Exchange 2000 contains a vulnerability that allows remote attackers to conduct a denial-of-service attack that once begun, cannot be stopped until the crafted message has been completely processed.

Description

Microsoft Exchange 2000 contains a vulnerability in its handling of RFC2822 message headers. If an attacker connects directly to the Exchange server and submits a crafted message containing certain invalid headers, Exchange will consume all available CPU resources to process the message. Due to the way that messages are queued on the Exchange server, restarting the Exchange service or rebooting the server will not remove the message from the queue; it must be completely processed before the server can process any other requests.

---

Impact

Attackers can conduct a denial-of-service attack that once begun, cannot be stopped until the crafted message has been completely processed.

---

Solution

Apply a patch from your vendor

Microsoft has released Microsoft Security Bulletin MS02-025 to address this issue. For more information, please see

http://www.microsoft.com/technet/security/bulletin/ms02-025.asp

---

Vendor Information

779163

Filter by status: All Affected Not Affected Unknown

Filter by content: __ Additional information available

__ Sort by: Status Alphabetical

Expand all

Javascript is disabled. Click here to view vendors.

Microsoft Corporation __ Affected

Notified: May 29, 2002 Updated: June 05, 2002

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

Microsoft has released Microsoft Security Bulletin MS02-025 to address this issue. For more information, please see

http://www.microsoft.com/technet/security/bulletin/ms02-025.asp

If you have feedback, comments, or additional information about this vulnerability, please send us [email](<mailto:[email protected]?Subject=VU%23779163 Feedback>).

CVSS Metrics

Group	Score	Vector
Base
Temporal
Environmental

References

• <http://www.microsoft.com/technet/security/bulletin/ms02-025.asp&gt;
• <http://www.ietf.org/rfc/rfc2822.txt&gt;
• <http://www.securityfocus.com/bid/4881&gt;

Acknowledgements

This vulnerability was discovered by researchers at the Johannes Gutenberg University in Mainz, Germany.

This document was written by Jeffrey P. Lanza based on information provided by Microsoft.

Other Information

CVE IDs:	CVE-2002-0368
Severity Metric:	6.30 Date Public: