Microsoft Vulnerability in HTTP.sys Could Allow Denial of Service

Notification Type: IBM Internet Security Systems Protection Alert
Notification Date: May 15, 2013
Notification Version: 1.0
Name: Microsoft Vulnerability in HTTP.sys Could Allow Denial of Service
Public disclosure/
In the wild date:
May 14, 2013
Aliases: MS13-039
CVE: CVE-2013-1305

A vulnerability exists in Microsoft Windows Server 2012 and Microsoft Windows 8 that if exploited successfully will cause denial of service.


ISS Coverage

Product Content Version
Proventia Network IDS
Proventia Network IPS
Proventia MFS
Proventia Server (Linux)
RealSecure Network
RealSecure Server Sensor
Virtual Server Protection for VMware
Proventia Desktop
Proventia Server IPS (Windows)
Propagation Techniques ISS Protection Available
Remote Exploit HTTP_IIS_Http_Sys_DoS*
15 May 2013

* This signature is NOT blocking by default.

Detailed Description

Business Impact:

An attacker could cause a vulnerable server to stop responding. This would result in the unavailability of services running on the server, such as business web sites and web applications not being available to internal users and customers.

*CVSS: Base Score: 7.8
  Access Vector: Network
Access Complexity: Low
Authentication: None
Confidentiality Impact: None
Integrity Impact: None
Availability Impact: Complete
Adjusted Temporal Score: 5.8
  Exploitability: Unproven
Remediation Level: Official-Fix
Report Confidence: Confirmed
Affected Products: For a full list of affected versions, see references below.
Technical Description

The vulnerability is in the HTTP protocol stack (HTTP.sys) and is triggered when handling a malicious HTTP header. An attacker who successfully exploits this vulnerability could trigger an infinite loop in the HTTP protocol stack.


A patch is available, see references below for details.



Revision History

1.0 Initial publication.

* According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.
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