[SA19284] avast! Antivirus Insecure Default File Permissions

TITLE:
avast! Antivirus Insecure Default File Permissions

SECUNIA ADVISORY ID:
SA19284

VERIFY ADVISORY:
http://secunia.com/advisories/19284/

CRITICAL:
Less critical

IMPACT:
Security Bypass, Manipulation of data, Privilege escalation

WHERE:
Local system

SOFTWARE:
avast! Antivirus 4.x
http://secunia.com/product/5162/

DESCRIPTION:
A security issue has been reported in avast! Antivirus, which can be
exploited by malicious, local users to bypass certain security
restrictions or gain escalated privileges.

The security issue is caused due to insecure default file permissions
being set on the installed files and folders. This allows any
non-privileged users on the system to remove the files or replace
them with malicious binaries.

Successful exploitation reportedly requires that the TEMP folder is
on the same drive as the avast! installation folder.

The security issue has been confirmed in avast! Professional Edition
version 4.6.763 with database 612-0 and also reported in the Home
Edition. Other versions may also be affected.

SOLUTION:
Restrict access to affected systems.

PROVIDED AND/OR DISCOVERED BY:
toadlife, hpguru

ORIGINAL ADVISORY:
http://forum.avast.com/index.php?topic=19862.0
http://www.dslreports.com/forum/remark,15601404~days=9999~start=20

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About:
This Advisory was delivered by Secunia as a free service to help
everybody keeping their systems up to date against the latest
vulnerabilities.

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