TITLE: Firefox Multiple Vulnerabilities

SECUNIA ADVISORY ID: SA20376

VERIFY ADVISORY: http://secunia.com/advisories/20376/

CRITICAL: Highly critical

IMPACT: Security Bypass, Cross Site Scripting, System access

WHERE: >From remote

SOFTWARE:
Mozilla Firefox 1.x
http://secunia.com/product/4227/
Mozilla Firefox 0.x
http://secunia.com/product/3256/

DESCRIPTION: Multiple vulnerabilities have been reported in Firefox, which can be exploited by malicious people to bypass certain security restrictions, conduct cross-site scripting and HTTP response smuggling attacks, and potentially compromise a user's system.

1) An error in the sandbox protection of JavaScript run via EvalInSandbox can be exploited to execute arbitrary JavaScript code with escalated privileges by calling the "valueOf()" function on external objects outside of the sandbox. Successful exploitation requires that the attacker is able to execute JavaScript code inside the EvalInSandbox (e.g. via a Proxy Autoconfig script or a third-party extension using the vulnerable functionality).

2) Some errors in the browser engine can be exploited to cause a memory corruption. Successful exploitation may allow execution of arbitrary code.

3) Two errors in the handling of specially crafted HTTP responses in certain situations can be exploited to cause the browser to process a response as two separate responses from different sites. Successful exploitation allows execution of arbitrary HTML and script in a user's browser session in context of an arbitrary site, but requires that the browser is configured to use a proxy or that the malicious site shares the same IP address as the targeted site.

4) Two errors in the handling of the "View Image" and "Show only this frame" functionalities can be exploited to execute arbitrary HTML and script code in a user's browser session in context of an arbitrary site by e.g. tricking a user into right-clicking and choosing "View Image" on a broken image.

5) An error caused due to persisted XUL attributes in certain situations being associated with an incorrect URL can be exploited to execute arbitrary JavaScript code with escalated privileges.

6) An error caused due to content-defined setters on an object prototype being called by privileged code in the user interface can be exploited to execute arbitrary JavaScript code with escalated privileges.

7) An error caused due to an off-by-two array boundary error in the "crypto.signText()" function can be exploited to cause a buffer overflow by passing optional Certificate Authority name arguments.

8) An error exists due to Unicode Byte-order-Mark (BOM) data being stripped from documents served in UTF-8 during the conversion to Unicode. This can be exploited to bypass certain HTML and JavaScript filtering mechanisms in web applications using the UTF-8 character encoding.

9) An error in the processing of the addSelectionListener when handling notifications in certain situations can be exploited to execute arbitrary JavaScript code with escalated privileges.

SOLUTION: Update to version 1.5.0.4.
http://www.mozilla.com/firefox/

PROVIDED AND/OR DISCOVERED BY:
1) moz_bug_r_a4
2) Mozilla Developers
3) Kazuho Oku, Cybozu Labs
4) Paul Nickerson
5) Jonas Sicking, Mozilla
6) Paul Nickerson and moz_bug_r_a4
7) Mikolaj J. Habryn
8) Masatoshi Kimura
9) moz_bug_r_a4

ORIGINAL ADVISORY:
1) http://www.mozilla.org/security/announce/2006/mfsa2006-31.html
2) http://www.mozilla.org/security/announce/2006/mfsa2006-32.html
3) http://www.mozilla.org/security/announce/2006/mfsa2006-33.html
4) http://www.mozilla.org/security/announce/2006/mfsa2006-34.html
5) http://www.mozilla.org/security/announce/2006/mfsa2006-35.html
6) http://www.mozilla.org/security/announce/2006/mfsa2006-37.html
7) http://www.mozilla.org/security/announce/2006/mfsa2006-38.html
8) http://www.mozilla.org/security/announce/2006/mfsa2006-42.html
9) http://www.mozilla.org/security/announce/2006/mfsa2006-43.html