Vulnerability Note VU#703835

Macromedia JRun ISAPI DLL filter vulnerable to buffer overflow via request for long Host header field

Original Release date: 29 May 2002 | Last revised: 09 Apr 2003


A remotely exploitable buffer overflow exists in Macromedia's JRun version 3.1 on Win32 platforms.


A remotely exploitable buffer overflow exists in the Win32 version of Macromedia's JRun version 3.1 on Win32 platforms.

JRun is an application server that works with most popular web servers such as Apache and IIS. Macromedia states that JRun is deployed at over 10,000 organizations worldwide.

As reported in the Next Generation Security Software Advisory (#NISR29052002), a remotely exploitable buffer overflow exists in the ISAPI filter/application. Specifically, the buffer overflow exists in the portion of code that handles the host header field. If an attacker sends a specially crafted request to the application server, he can overwrite a return address on the stack. Because the vulnerable DLL is running in the address space of the web server process (at least on IIS 4 & 5), code submitted by the attacker will be run with SYSTEM privileges.


A remote attacker can execute arbitrary code on the vulnerable target with SYSTEM privileges.


Apply the patch from Macromedia Inc. or upgrade to JRun 4.


Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Macromedia Inc.Affected29 May 200229 May 2002
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



This vulnerability was discovered by David Litchfield of Next Generation Security Software .

This document was written by Ian A. Finlay.

Other Information

  • CVE IDs: CAN-2002-0801
  • Date Public: 29 May 2002
  • Date First Published: 29 May 2002
  • Date Last Updated: 09 Apr 2003
  • Severity Metric: 54.00
  • Document Revision: 53


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