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Gentoo Linux Security Advisory GLSA 200511-17 |
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http://security.gentoo.org/ |
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Severity: Normal |
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Title: FUSE: mtab corruption through fusermount |
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Date: November 22, 2005 |
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Bugs: #112902 |
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ID: 200511-17 |
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Synopsis |
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======== |
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|
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The fusermount utility from FUSE can be abused to corrupt the /etc/mtab |
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file contents, potentially allowing a local attacker to set |
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unauthorized mount options. |
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Background |
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========== |
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|
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FUSE (Filesystem in Userspace) allows implementation of a fully |
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functional filesystem in a userspace program. The fusermount utility is |
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used to mount/unmount FUSE file systems. |
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|
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Affected packages |
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================= |
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|
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------------------------------------------------------------------- |
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Package / Vulnerable / Unaffected |
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------------------------------------------------------------------- |
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1 sys-fs/fuse < 2.4.1-r1 >= 2.4.1-r1 |
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Description |
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=========== |
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|
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Thomas Biege discovered that fusermount fails to securely handle |
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special characters specified in mount points. |
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|
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Impact |
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====== |
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|
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A local attacker could corrupt the contents of the /etc/mtab file by |
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mounting over a maliciously-named directory using fusermount, |
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potentially allowing the attacker to set unauthorized mount options. |
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This is possible only if fusermount is installed setuid root, which is |
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the default in Gentoo. |
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|
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Workaround |
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========== |
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There is no known workaround at this time. |
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Resolution |
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========== |
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All FUSE users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=sys-fs/fuse-2.4.1-r1" |
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References |
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========== |
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[ 1 ] CVE-2005-3531 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-3531 |
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|
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Availability |
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============ |
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|
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This GLSA and any updates to it are available for viewing at |
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the Gentoo Security Website: |
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http://security.gentoo.org/glsa/glsa-200511-17.xml |
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Concerns? |
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========= |
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Security is a primary focus of Gentoo Linux and ensuring the |
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confidentiality and security of our users machines is of utmost |
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importance to us. Any security concerns should be addressed to |
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security@g.o or alternatively, you may file a bug at |
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http://bugs.gentoo.org. |
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License |
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======= |
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Copyright 2005 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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|
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The contents of this document are licensed under the |
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Creative Commons - Attribution / Share Alike license. |
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http://creativecommons.org/licenses/by-sa/2.0 |
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