JVN#45675516 Flash Player vulnerable in handling cross-domain policy files

Overview

Adobe Flash Player contains a vulnerability caused by improper handling of cross-domain policy files.

Products Affected

Flash Player 7.0.70.0 and earlier
Flash Player 8.0.35.0 and earlier
Flash Player 9.0.48.0 and earlier

For details, see the information provided by the vendor.

Description

Adobe Flash Player is a player for the Flash media format and enables frame-based animations with sound to be viewed within a web browser.
According to Adobe's "About allowing cross-domain data loading", "When a Flash document attempts to access data from another domain, Flash Player automatically attempts to load a policy file from that domain. If the domain of the Flash document that is attempting to access the data is included in the policy file, the data is automatically accessible."
Flash Player contains a vulnerability that may allow a specially crafted web page to be interpreted as a cross-domain policy file because the plugin fails to properly handle cross-domain policy files.

Impact

Cross-domain policy restrictions can be bypassed by using a specially crafted web page. This could result in unauthorized access to website data contrary to the website administrator's intent.

Solution

Update the Software
For Flash Player 8.x or Flash Player 9.x
Apply the latest updates provided by the vendor.

Apply the Patch
For Flash Player 7.x
Apply the appropriate patch as specified in the Flash Player update TechNote provided by the vendor.
The vendor has announced that they discontinued the support of Flash Player 7.x and will no longer provide security updates after this update. Those who are unable to upgrade to Flash Player 8.x or 9.x and wish to continue to use Flash Player 7.x can find the archived installers in the Archived Flash Player TechNote.

For more information, refer to the vendor's website

Vendor Status

Vendor	Link
Adobe	Flash Player Update available to Address Security Vulnerabilities
	Security bulletins and advisories
	Security changes in Flash Player 9

References

JPCERT/CC Addendum

Vulnerability Analysis by JPCERT/CC

Analyzed on 2007.12.20

Measures	Conditions	Severity
Access Required	Routed - can be attacked over the Internet using packets	High
Authentication	None - anonymous or no authentication (IP addresses do not count)	High
User Interaction Required	Simple - the user must be convinced to take a standard action that does not feel harmful to most users, such as click on a link or view a file	Medium
Exploit Complexity	Low-Medium - some expertise and/or luck required (most buffer overflows, guessing correctly in small space, expertise in Windows function calls)	Medium-High

Description of each analysis measures

Credit

Toshiharu Sugiyama of UBsecure, Inc. reported this vulnerability to IPA.
JPCERT/CC coordinated with the vendors under Information Security Early Warning Partnership.

Other Information

JPCERT Alert
JPCERT Reports
CERT Advisory
CPNI Advisory
TRnotes
CVE	CVE-2007-6243
JVN iPedia	JVNDB-2007-000817