Google and BlackBerry have acknowledged that certain Android phones and BBM are vulnerable to Heartbleed, a bug affecting up to two-thirds of the internet.
Android phones running 4.1.1 Jelly Bean are vulnerable but all other versions of Android appear immune to the issue. Google's resources list 4.1.x as powering 34 per cent of all Android devices.
Heartbleed could allow a malicious party to query sensitive data within a mobile browser. For example, an attacker could load malware into one tab and use it to steal bank data from another tab open to a user's banking site. They could not steal data from other apps because of Android's design.
"If you have a vulnerable device and there's no fix available for you, I would be very cautious about using that device for sensitive data," security researcher Marc Rodgers told Ars Technica.
Google says it is working on distributing fixes to Android partners. However, this places the burden of updating affected phones on OEM partners who often do not send patches. Adoption rates for new versions of Android are notoriously low.
BlackBerry is working on a fix for its services as well. It plans to release a patch for BlackBerry Messenger for Android and iOS to fix Heartbleed by Friday.
While most BlackBerry services do not use OpenSSL (the encryption compromised by Heartbleed), the company does use it with BBM and Secure Work Space corporate mail.
"The level of risk here is extremely small," said BlackBerry senior vice president Scott Totzke. "It's a very complex attack that has to be timed in a very small window."
BlackBerry's website claims its services are still secure, even with the bug. It says BBM and Secure Work Space are designed to connect only to "a known and trusted end point."
Heartbleed has rocked the web, as it compromises OpenSSL. OpenSSL is used as the basic encryption service in HTTPS, TLS, and other online services.
To check if your phone is affected by Heartbleed, download the Heartbleed Detector from Lookout Mobile Security.
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