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ncompress insecure temporary file creation

Vendor: ftp://ftp.leo.org/pub/comp/os/unix/linux/sunsite/utils/compress/
Advisory: http://www.zataz.net/adviso/ncompress-09052005.txt
Vendor informed: yes
Exploit available: yes
Impact : low
Exploitation : low

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The vulnerability is caused due to temporary file being created insecurely.
This can be exploited via symlink attacks in combination with a race
condition to create and overwrite arbitrary files
with the privileges of the user running the affected script.

Secunia has reported that D1g1t4lLeech has discovered this bug
the 2005-09-16

ZATAZ Audit has discovered this bug the 2005-09-05

D1g1t4lLeech is a true Leecher :)

Gentoo Security take care on your IRC Channel, spy everywhere.

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Versions:
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ncompress <= 4.2.4-r1

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Solution:
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To prevent symlink attack use kernel patch such as grsecurity

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Timeline:
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Discovered : 2005-09-05
Vendor notified : 2005-09-05
Vendor response : no reponse
Vendor fix : no patch
Vendor Sec report (vendor-sec@lst.de) :
Disclosure :

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Technical details :
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ncompress use vulnerable version off zdiff and zcmp.

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Related :
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Secunia : http://secunia.com/advisories/13131/
CVE : CAN-2004-0970

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Credits :
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Eric Romang (eromang@zataz.net - ZATAZ Audit)
Thxs to Gentoo Security Team. (Taviso, jaervosz, solar, Koon, etc.)