Researchers warn that the Pinterest and Yammer social networking applications for iOS fail to validate server certificates, allowing malicious actors to eavesdrop on users’ communications. New versions of the apps have been released to address the issue.
The vulnerability, reported earlier this week by the Dutch security firm Securify, allows a remote attacker to steal users’ passwords through a man-in-the-middle (MitM) attack. One scenario in which the security bug can be exploited is when the targeted user relies on an unsecured Wi-Fi network to access the Internet, experts noted.
Securify said Pinterest didn’t respond to their emails regarding the issue. However, a Pinterest spokesperson told SecurityWeek that the bug was previously brought to the company’s attention and they began working on it immediately.
Pinterest addressed the MitM vulnerability with the release of version 4.5.1 of the iOS app. Yammer, which is owned by Microsoft, released version 6.4.26 to patch the flaw. Securify advises users to update their applications and change their passwords as a precaution.
“Implementing proper SSL validation is a significant pitfall for app developers. In some libraries that involve SSL, the default server certificate validation is disabled during development to test the app against a test environment which in general has an invalid certificate. This is equivalent to trusting all certificates,” Han Sahin, co-founder of Securify, told SecurityWeek via email. “Developers often forget to remove this debugging logic before uploading the app to the market, which results in a lot of apps being vulnerable to MitM attacks, even major brands.”
The expert has pointed out that development libraries can also be problematic. A good example is the AFNetworking networking library for iOS and Mac OS X. Researchers discovered recently that the library was plagued by an MitM flaw.
The issue has been resolved with the release of AFNetworking 2.5.2, but the existence of the security hole shows that app developers have to actively monitor all the libraries used by their apps, Sahin said.
Last month, Securify published advisories for several vulnerabilities found in EMC products. The flaws were addressed before their details were disclosed by the security firm.