Summaryinfo

A vulnerability marked as critical has been reported in Microsoft Skype 3.2.0.6673 on Android. The impacted element is an unknown function of the component Lockscreen. The manipulation leads to improper authentication. Furthermore, an exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Microsoft Skype 3.2.0.6673 on Android (Unified Communication Software). This issue affects an unknown code of the component Lockscreen. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is confidentiality, integrity, and availability.

The weakness was published 07/01/2013 by Emilio Lopez and Pulser as not defined mailinglist post (Full-Disclosure). It is possible to read the advisory at seclists.org. The vendor was not involved in the public release. The exploitation is known to be easy. Attacking locally is a requirement. No form of authentication is needed for a successful exploitation. Technical details are unknown but a public exploit is available. The advisory points out:

Tested with Skype version 3.2.0.6673 (released 1st July 2013) on various Android devices (Sony Xperia Z, Samsung Galaxy Note 2, Huawei Premia 4G

After immediately, there has been an exploit disclosed. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $5k-$25k. The advisory illustrates:

1. Initiate a Skype call to the target device, which will cause it to wake, ring, and display a prompt on the screen to answer or reject the call, 2. Accept the call from the target device using the sreen answer button on the screen, 3. End the call from the initiating device (ie. the device used to call the target phone), 4. The target device will end the call, and should display the lockscreen, 5. Turn off the screen of the target device using the power key, and turn it on again, 6. The lockscreen will now be bypassed. It will remain bypassed until the device is rebooted

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at OSVDB (94794†). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Unified Communication Software

Vendor

• Microsoft

Name

• Skype

Version

• 3.2.0.6673

License

• free

Website

• Vendor: https://www.microsoft.com/

CPE 2.3info

• 🔍

CPE 2.2info

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