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Home >> Browse Vulnerability Assessment Database >> Gentoo Local Security Checks >> [GLSA-200405-19] Opera telnet URI handler file creation/truncation vulnerability

Vulnerability Assessment Details

[GLSA-200405-19] Opera telnet URI handler file creation/truncation vulnerability

Vulnerability Assessment Summary
Opera telnet URI handler file creation/truncation vulnerability

Detailed Explanation for this Vulnerability Assessment
The remote host is affected by the vulnerability described in GLSA-200405-19
(Opera telnet URI handler file creation/truncation vulnerability)

The telnet URI handler in Opera does not check for leading '-' characters
in the host name. Consequently, a maliciously-crafted telnet:// link may be
able to pass options to the telnet program itself. One example would be the
following:
telnet://-nMyFile
If MyFile exists in the user's home directory and the user clicking on the
link has write permissions to it, the contents of the file will be
overwritten with the output of the telnet trace information. If MyFile does
not exist, the file will be created in the user's home directory.

Impact

This exploit has two possible impacts. First, it may create new files in
the user's home directory. Second, and far more serious, it may overwrite
existing files that the user has write permissions to. A possible hacker with
some knowledge of a user's home directory might be able to destroy
important files stored within.

Workaround

Disable the telnet URI handler from within Opera.

References:
http://www.idefense.com/application/poi/display?id=104&type=vulnerabilities&flashstatus=true

Solution:
All Opera users are encouraged to upgrade to the latest version of the
program:
# emerge sync
# emerge -pv ">=net-www/opera-7.50_beta1"
# emerge ">=net-www/opera-7.50_beta1"

Network Security Threat Level: Medium

Networks Security ID:

Vulnerability Assessment Copyright: (C) 2005 Michel Arboi

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