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Gentoo Linux Security Advisory GLSA 200512-17 |
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http://security.gentoo.org/ |
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Severity: High |
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Title: scponly: Multiple privilege escalation issues |
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Date: December 29, 2005 |
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Bugs: #116526 |
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ID: 200512-17 |
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Synopsis |
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======== |
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|
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Local users can exploit an scponly flaw to gain root privileges, and |
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scponly restricted users can use another vulnerability to evade shell |
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restrictions. |
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Background |
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========== |
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|
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scponly is a restricted shell, allowing only a few predefined commands. |
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It is often used as a complement to OpenSSH to provide access to remote |
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users without providing any remote execution privileges. |
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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 net-misc/scponly < 4.2 >= 4.2 |
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Description |
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=========== |
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|
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Max Vozeler discovered that the scponlyc command allows users to chroot |
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into arbitrary directories. Furthermore, Pekka Pessi reported that |
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scponly insufficiently validates command-line parameters to a scp or |
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rsync command. |
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Impact |
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====== |
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|
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A local attacker could gain root privileges by chrooting into arbitrary |
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directories containing hardlinks to setuid programs. A remote scponly |
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user could also send malicious parameters to a scp or rsync command |
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that would allow to escape the shell restrictions and execute arbitrary |
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programs. |
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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 scponly users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=net-misc/scponly-4.2" |
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References |
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========== |
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[ 1 ] scponly release notes |
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http://sublimation.org/scponly/index.html#relnotes |
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Availability |
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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-200512-17.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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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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