Gentoo: Mgetty Insecure temporary file usage
Posted by Benjamin D. Thomas   
Gentoo =3D=3D=3D=3D=3D=3D=3D=3D Mgetty uses temporary files in an insecure manner, allowing for symlink attacks.
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Gentoo Linux Security Advisory                           GLSA 200812-08
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                                              http://security.gentoo.org/=

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    Severity: Normal
       Title: Mgetty: Insecure temporary file usage
        Date: December 06, 2008
        Bugs: #235806
          ID: 200812-08

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Synopsis
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Mgetty uses temporary files in an insecure manner, allowing for symlink
attacks.

Background
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Mgetty is a set of fax and voice modem programs.

Affected packages
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       Package            /   Vulnerable   /                  Unaffected
      -------------------------------------------------------------------=

    1  net-dialup/mgetty      < 1.1.36-r2                   >=3D 1.1.36-r=
2

Description
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Dmitry E. Oboukhov reported that the "spooldir" directory in
fax/faxspool.in is created in an insecure manner.

Impact
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A local attacker could exploit this vulnerability to overwrite
arbitrary files with the privileges of the user running the
application.

Workaround
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There is no known workaround at this time.

Resolution
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All Mgetty users should upgrade to the latest version:

      # emerge --sync
      # emerge --ask --oneshot --verbose ">=3Dnet-dialup/mgetty-1.1.36-r2=
"

References
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    [ 1 ] CVE-2008-4936
          http://cve.mitre.org/cgi-bin/cvename.cgi?name=3DCVE-2008-4936

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-200812-08.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 2008 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