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Submission + - Duo Security iOS App Vulnerability

dajjhman writes: Duo Security put out a PSA today informing users that their iOS application has not been checking the validity of SSL certificate domain names.
For those unfamiliar, Duo Security provides a 2 factor authentication system known for its implementation of push notifications to approve login requests. It is found in numerous applications, ranging from personal use to large enterprises
The vulnerability, identified as DUO-PSA-2015-002, allows attackers to use a Man in the Middle attack to see all of the network data. This was caused by a bug in a 3rd party library they used, and the announcement came along with an update to the App Store.
Duo says that due to the nature of their client-server communications, there was little risk an attacker could activate a push request as there is a client key. The PSA has not been posted to their blog at the time of this writing, but it is reproduced below.
The advisory is signed with the Duo Security PSIRT PGP key which is available from their security contact page.

Hash: SHA256

Duo Product Security Advisory

Advisory ID: DUO-PSA-2015-002
Publication Date: 2015-04-06
Revision Date: 2015-04-13
Status: Fixed
Document Revision: 2


Duo Security has identified an issue in recent versions of Duo Mobile for iOS that could allow attackers to perform a successful Man-in-the-Middle (MITM) attack against the app's TLS connections, if they can otherwise manipulate the network traffic exchanged between the mobile app and Duo's cloud service.

This issue has been fixed in Duo Mobile 3.7.1; all iOS users should update as soon as possible.


On the iOS platform, Duo Mobile leverages AFNetworking — a widely-used third-party HTTP client library — to communicate with Duo's cloud service. Recently, it was determined that AFNetworking did not validate digital certificates against server hostnames by default. As a result, Duo Mobile would e.g. consider a digital certificate for "" as valid for "" when establishing a TLS tunnel.

This behavior makes it possible for an attacker to perform a successful Man-in-the-Middle (MITM) attack against TLS connections from affected versions of Duo Mobile, if he can otherwise manipulate the network traffic exchanged between the mobile app and Duo's cloud service. This might be a risk, for example, when using Duo Mobile while connected to untrusted wi-fi networks.

However, in addition to TLS, Duo Mobile uses application-level signatures to ensure the integrity and authenticity of requests sent from Duo Mobile to Duo's service. Becauses of this mechanism, a MITM attack would still not generally allow an attacker to e.g. approve a fraudulent Duo Push authentication request.

Note: A different vulnerability was introduced into AFNetworking in version 2.5.1, and recently gained widespread attention ( Duo Mobile currently uses AFNetworking version 2.3.1, and was therefore not affected by that particular vulnerability. This is a separate — if very similar — issue.


An attacker can perform a successful Man-in-the-Middle (MITM) attack against Duo Mobile's TLS connections if he can otherwise manipulate the network traffic exchanged between the mobile app and Duo's cloud service. Duo's application-level signing mechanism still generally prevents the attacker from e.g. approving fraudulent Duo Push authentication requests. However, there are some limitations to this technique:

* Duo Mobile cannot use application-level signatures when setting up a new account, because — at this point — the app has not yet negotiated a key-pair with Duo's service. If an attacker intercepted traffic from Duo Mobile during this process, he could gain the ability to generate valid one-time passcodes and exert full control over subsequent Duo Push authentication requests intended for the targeted device.

* Requests from Duo Mobile to Duo's service have application-level signatures, but responses from the service do not. It may therefore be feasible for an attacker to manipulate details of a fraudulent authentication request such that it appears legitimate, thereby tricking a user into approving it.

Affected Product(s)

* Duo Mobile for iOS, versions 3.4 — 3.7


Duo Mobile 3.7.1 was published to the iTunes App Store on April 6, 2015. This version ensures that certificate domain-name validation is performed for all TLS connections.

Users should upgrade to this version immediately to prevent the issues described above. Note that administrators can audit their users' Duo Mobile app versions in the "phones" section of the Duo administrative interface.

As noted above, there is a small risk that users' Duo Mobile credentials could be compromised, if an attacker captured network traffic from Duo Mobile during account setup. After users have upgraded, administrators may choose to forcibly invalidate any existing credentials by re-activating users' Duo Mobile accounts in the administrative interface.

Vulnerability Metrics

Vulnerability Class: Improper Certificate Validation (CWE-295)
Remotely Exploitable: Yes
Authentication Required: No
Severity: High
CVSSv2 Overall Score: 5.8
CVSSv2 Group Scores: Base: 6.8, Temporal: 5.9, Environmental: 5.8


* CWE-295: Improper Certificate Validation —
* AFNetworking issue #2619 —
* Heartbleed Defense-in-Depth Part #2: Don't Trust SSL —


* Engineers at Duo internally discover that Duo Mobile for iOS does not correctly validate server certificates.
* Duo develops a fix and submits an updated Duo Mobile 3.7.1 to the iTunes App Store.

* Duo Mobile for iOS version 3.7.1 is approved by Apple

* Duo completes testing on Duo Mobile for iOS 3.7.1 and releases it to end users.
* Duo drafts advisory and shares it with affected Enterprise and Business customers.

* Duo updates advisory and shares it with all remaining customers.


Technical questions regarding this issue should be sent to and reference "DUO-PSA-2015-002" in the subject.

Other feedback regarding this issue can be sent to


Comment Re: Lifestyle - Canada (Score 1) 332

The statistics are about "total water withdrawal", where "some portion may be returned for further use downstream". I guess that the water used to produce hydro-electriciy could be counted as water withdrawn.

In that case, since Canada is producing a lot of hydro-electric power, it could impact the statistics.

Tar sands, on the other hand, although an important source of water pollution, seems to come up to approximately 10 m3/capita/year. In this case, not the culprit...

Comment Re:2 way street (Score 1) 335

If the "people doing the hiring" were all honest, efficient, unbiased people, then you'd be right right.

Most likely, though, this will facilitate discrimination by systematically rejecting arabs or blacks, but hide it behind a "screening process" that highlights those mistakes...

Plus the fact that people coming from poorer and harsher environments (immigrants and minorities, mostly) have more chances of finding their mistakes online than ivy-league offsprings. Redemption will become even harder for them.

GNOME 3.8 Released Featuring New "Classic" Mode 267

Hot on the heels of the Gtk+ 3.8 release comes GNOME 3.8. There are a few general UI improvements, but the highlight for many is the new Classic mode that replaces fallback. Instead of using code based on the old GNOME panel, Classic emulates the feel of GNOME 2 through Shell extensions (just like Linux Mint's Cinnamon interface). From the release notes: "Classic mode is a new feature for those people who prefer a more traditional desktop experience. Built entirely from GNOME 3 technologies, it adds a number of features such as an application menu, a places menu and a window switcher along the bottom of the screen. Each of these features can be used individually or in combination with other GNOME extensions."

Google Pledges Not To Sue Any Open Source Projects Using Their Patents 153

sfcrazy writes "Google has announced the Open Patent Non-Assertion (OPN) Pledge. In the pledge Google says that they will not sue any user, distributor, or developer of Open Source software on specified patents, unless first attacked. Under this pledge, Google is starting off with 10 patents relating to MapReduce, a computing model for processing large data sets first developed at Google. Google says that over time they intend to expand the set of Google's patents covered by the pledge to other technologies." This is in addition to the Open Invention Network, and their general work toward reforming the patent system. The patents covered in the OPN will be free to use in Free/Open Source software for the life of the patent, even if Google should transfer ownership to another party. Read the text of the pledge. It appears that interaction with non-copyleft licenses (MIT/BSD/Apache) is a bit weird: if you create a non-free fork it appears you are no longer covered under the pledge.

Submission + - Microsoft Seeks Patent for 'Search by Sketch'

theodp writes: So, how does one search for images that aren't tagged with keywords? Google does offer its sometimes-spotty search by image, but what if you don't have an image handy that looks like what you're searching for? Microsoft, reports GeekWire, offers a solution that's 'a little like playing Pictionary with a search engine — drawing a sketch and seeing if the algorithm can return pictures that match it.' That’s the concept behind Microsoft Research's patent-pending 'MindFinder' project, which has already been incorporated into a Windows Phone app called Sketch Match. A patent application made public Thursday notes that touch computing makes sketching easier than ever, making one wonder if we'll be 'giving Bing the finger' with Windows 8!

Comment Missclassified (Score 1) 219

This should have been classified under "YRO", not "Science".

Science disappeared a long time ago from Canada's tar sands industry discussions.

The Alberta and the Canadian governments try to call their approach "scientific" (a MP even used the expressions "based on facts" when talking about the conservatives' agenda - hilarious!) while forbidding scientists to present the results of their research, cutting their fundings and replacing their voices with marketing.

Work expands to fill the time available. -- Cyril Northcote Parkinson, "The Economist", 1955