Gentoo Archives: gentoo-announce

From: Kurt Lieber <klieber@g.o>
To: gentoo-announce@l.g.o
Cc: bugtraq@×××××××××××××.com, full-disclosure@××××××××××××.com, security-alerts@×××××××××××××.com
Subject: [gentoo-announce] [ GLSA 200405-19 ] Opera telnet URI handler file creation/truncation vulnerability
Date: Tue, 25 May 2004 16:44:15
Message-Id: 20040525155929.GA3228@mail.lieber.org
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2 Gentoo Linux Security Advisory GLSA 200405-19
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4 http://security.gentoo.org/
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6
7 Severity: Normal
8 Title: Opera telnet URI handler file creation/truncation
9 vulnerability
10 Date: May 25, 2004
11 Bugs: #50857
12 ID: 200405-19
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15
16 Synopsis
17 ========
18
19 A vulnerability exists in Opera's telnet URI handler that may allow a
20 remote attacker to overwrite arbitrary files.
21
22 Background
23 ==========
24
25 Opera is a multi-platform web browser.
26
27 Affected packages
28 =================
29
30 -------------------------------------------------------------------
31 Package / Vulnerable / Unaffected
32 -------------------------------------------------------------------
33 1 net-www/opera < 7.50_beta1 >= 7.50_beta1
34
35 Description
36 ===========
37
38 The telnet URI handler in Opera does not check for leading '-'
39 characters in the host name. Consequently, a maliciously-crafted
40 telnet:// link may be able to pass options to the telnet program
41 itself. One example would be the following:
42
43 telnet://-nMyFile
44
45 If MyFile exists in the user's home directory and the user clicking on
46 the link has write permissions to it, the contents of the file will be
47 overwritten with the output of the telnet trace information. If MyFile
48 does not exist, the file will be created in the user's home directory.
49
50 Impact
51 ======
52
53 This exploit has two possible impacts. First, it may create new files
54 in the user's home directory. Second, and far more serious, it may
55 overwrite existing files that the user has write permissions to. An
56 attacker with some knowledge of a user's home directory might be able
57 to destroy important files stored within.
58
59 Workaround
60 ==========
61
62 Disable the telnet URI handler from within Opera.
63
64 Resolution
65 ==========
66
67 All Opera users are encouraged to upgrade to the latest version of the
68 program:
69
70 # emerge sync
71
72 # emerge -pv ">=net-www/opera-7.50_beta1"
73 # emerge ">=net-www/opera-7.50_beta1"
74
75 References
76 ==========
77
78 [ 1 ] iDEFENSE Security Advisory 05.12.04
79 http://www.idefense.com/application/poi/display?id=104&type=vulnerabilities&flashstatus=true
80
81 Availability
82 ============
83
84 This GLSA and any updates to it are available for viewing at
85 the Gentoo Security Website:
86
87 http://security.gentoo.org/glsa/glsa-200405-19.xml
88
89 Concerns?
90 =========
91
92 Security is a primary focus of Gentoo Linux and ensuring the
93 confidentiality and security of our users machines is of utmost
94 importance to us. Any security concerns should be addressed to
95 security@g.o or alternatively, you may file a bug at
96 http://bugs.gentoo.org.
97
98 License
99 =======
100
101 Copyright 2004 Gentoo Technologies, Inc; referenced text
102 belongs to its owner(s).
103
104 The contents of this document are licensed under the
105 Creative Commons - Attribution / Share Alike license.
106
107 http://creativecommons.org/licenses/by-sa/1.0