scponly: Multiple privilege escalation issues
1.
Gentoo Linux Security Advisory
Version Information
| Advisory Reference |
GLSA 200512-17 / scponly |
| Release Date |
December 29, 2005 |
| Latest Revision |
May 22, 2006: 02 |
| Impact |
high |
| Exploitable |
local and remote |
| Package |
Vulnerable versions |
Unaffected versions |
Architecture(s) |
| net-misc/scponly |
<
4.2 |
>=
4.2 |
All supported architectures
|
Related bugreports:
#116526
Synopsis
Local users can exploit an scponly flaw to gain root privileges, and
scponly restricted users can use another vulnerability to evade shell
restrictions.
2.
Impact Information
Background
scponly is a restricted shell, allowing only a few predefined commands.
It is often used as a complement to OpenSSH to provide access to remote
users without providing any remote execution privileges.
Description
Max Vozeler discovered that the scponlyc command allows users to chroot
into arbitrary directories. Furthermore, Pekka Pessi reported that
scponly insufficiently validates command-line parameters to a scp or
rsync command.
Impact
A local attacker could gain root privileges by chrooting into arbitrary
directories containing hardlinks to setuid programs. A remote scponly
user could also send malicious parameters to a scp or rsync command
that would allow to escape the shell restrictions and execute arbitrary
programs.
3.
Resolution Information
Workaround
There is no known workaround at this time.
Resolution
All scponly users should upgrade to the latest version:
Code Listing 3.1: Resolution |
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-misc/scponly-4.2"
|
4.
References
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