ZDI-10-028: Skype URI Processing Arbitrary XML File Deletion Vulnerability

ZDI-10-028: Skype URI Processing Arbitrary XML File Deletion Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-028
March 11, 2010

– Affected Vendors:
Skype

– Affected Products:
Skype

– TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 8329.
For further product information on the TippingPoint IPS, visit:

http://www.tippingpoint.com

– Vulnerability Details:
This vulnerability allows remote attackers to remove arbitrary XML files
on vulnerable installations of Skype. User interaction is required to
exploit this vulnerability in that the target must visit a malicious
page.

The specific flaw exists in Skype's handling of the 'skype-plugin:'
protocol. An attacker can specify a malicious URI, that upon clicking,
will trigger the deletion of an arbitrary attacker specified XML file.

– Vendor Response:
Not available.

– Disclosure Timeline:
2009-07-14 - Initial report to vendor, no response.
2010-01-07 - Follow-up report, again no response.
2010-01-11 - Received support e-mail with update notice from Skype.
2010-01-11 - We responded the same day stating that the new version does not address our reported bugs.
2010-01-12 - Skype requests more details, specifically a screen shot.
2010-01-12 - We responded the same day. No follow-up response from Skype.
2010-01-19 - We followed up with Skype again who has not been heard from since.
2010-03-11 - Uncoordinated release of public advisory due to failure to communicate, issue remains unresolved.

– Credit:
This vulnerability was discovered by:
* rgod

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