Gentoo: ModSecurity Denial of Service
Posted by Benjamin D. Thomas   
Gentoo =3D=3D=3D=3D=3D=3D=3D=3D Two vulnerabilities in ModSecurity might lead to a Denial of Service.
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Gentoo Linux Security Advisory                           GLSA 200907-02
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                                            http://security.gentoo.org/
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  Severity: Normal
     Title: ModSecurity: Denial of Service
      Date: July 02, 2009
      Bugs: #262302
        ID: 200907-02

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Synopsis
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Two vulnerabilities in ModSecurity might lead to a Denial of Service.

Background
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ModSecurity is a popular web application firewall for the Apache HTTP
server.

Affected packages
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    -------------------------------------------------------------------
     Package                  /  Vulnerable  /              Unaffected
    -------------------------------------------------------------------
  1  www-apache/mod_security       < 2.5.9                    >=3D 2.5.9

Description
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Multiple vulnerabilities were discovered in ModSecurity:

* Juan Galiana Lara of ISecAuditors discovered a NULL pointer
  dereference when processing multipart requests without a part header
  name (CVE-2009-1902).

* Steve Grubb of Red Hat reported that the "PDF XSS protection"
  feature does not properly handle HTTP requests to a PDF file that do
  not use the GET method (CVE-2009-1903).

Impact
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A remote attacker might send requests containing specially crafted
multipart data or send certain requests to access a PDF file, possibly
resulting in a Denial of Service (crash) of the Apache HTTP daemon.
NOTE: The PDF XSS protection is not enabled by default.

Workaround
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There is no known workaround at this time.

Resolution
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All ModSecurity users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=3Dwww-apache/mod_security-2.5.9"

References
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  [ 1 ] CVE-2009-1902
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=3DCVE-2009-1902
  [ 2 ] CVE-2009-1903
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=3DCVE-2009-1903

Availability
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This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

  http://security.gentoo.org/glsa/glsa-200907-02.xml

Concerns?
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Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
http://bugs.gentoo.org.

License
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Copyright 2009 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

http://creativecommons.org/licenses/by-sa/2.5