Google has recently confirmed that there is a serious issue with improper seeding of the pseudo-random number generator (PRNG) found on some versions of the Android platform. As a result, we've released a new version of SQLCipher for Android which addresses potential risks introduced by this vulnerability. SQLCipher for Android 2.2.2 binaries can be found here.
The issue itself centers around improper default initialization of the OpenSSL PRNG; specifically, it appears from the fix that /dev/urandom was not included in the seeding process to the entropy pool. This increases the likelihood that low-entropy data could be provided when requesting random data from calls to OpenSSL’s RAND_bytes.
Previously, SQLCipher for Android was dynamically linking the system provided version of the OpenSSL library on the device. This means that SQLCipher was using the version of OpenSSL on affected platforms. This reduced complexity and allowed for a smaller binary payload when integrating the library into an application. Unfortunately, it also means that older versions of SQLCipher used the affected versions of OpenSSL on those Android versions.
To address this issue, SQLCipher for Android will no longer rely on Android’s system-provided OpenSSL library. Instead, new binaries statically link the 1.0.1e tag of OpenSSL, currently the latest release. We have verified locally that OpenSSL 1.0.1e includes data from /dev/urandom in the entropy pool during initialization. This change has the added benefit of normalizing behavior, as there are outdated distributions of OpenSSL embedded in certain Android platforms. We estimate that the statically linked library will add 1.0 MB to most ARM-only applications, although it could be as high as an additional 2.3 MB if other architectures are supported (e.g., x86).
SQLCipher relies on random data for two purposes: initial generation of the random database salt, and generation of per-page initialization vectors (IVs) for AES-256-CBC encryption. Happily, neither usage will result in catastrophic failure, as was the case with Bitcoin wallet applications, where poor randomness led to the generation of weak asymmetric keys. That said, it is likely that existing databases created on older Android platforms will have low-entropy salts and IVs. Theoretically this weakness in the underlying PRNG could facilitate optimized attacks in certain circumstances.
As a result, we strongly recommend that you upgrade to the latest SQLCipher for Android binaries as soon as possible. Out of an abundance of caution, we’d also recommend that those concerned with the security of existing databases generated on affected Android platforms perform a database export via the sqlcipher_export convenience function to re-encrypt the database. This process will generate a new random database salt and initialization vectors for all pages in the database.
If you have any questions, please feel free to ask. Thanks!
This Thursday night, August 22nd at 10pm EDT, Tempo and other web systems will be temporarily unavailable while we perform critical patch updates to ensure the stability of our services.
This maintenance outage will also affect the Tempo API, the the Connect website, and the site for Codebook.
Down time could last up to 1 hour, however we hope it will be completed much more quickly. If you need to get in touch with us for any reason, please don’t hesitate.
STRIP for OS X version 2.0.2 is now available in the Mac App Store, providing numerous bug fixes and adjustments. We recommend all customers install this update. Among the changes in this release:
- Fixes disabled editor due to untitled labels
- Fixes persistence of changes to fields and sort order
- Fixes crash on login when last-accessed entry is no longer available
- Fixes display of WiFi sync service status in Preferences after launch
- Fixes add field control on first launch creating untitled label
- Fixes crash on export due to untitled labels
Customers who're using the version of STRIP for OS X purchased from the Zetetic store will also see the update shortly. Select the STRIP menu and choose "Check for Updates" if automatic update checking is disabled under Preferences.
This Thursday night, July 18th at 10pm EDT, Tempo and other web systems will be temporarily unavailable while we perform critical patch updates to ensure the stability of our services.
This maintenance outage will also affect the Tempo API, the the Connect website, and the site for Codebook.
Down time could last up to 1 hour, however we hope it will be completed much more quickly. If you need to get in touch with us for any reason, please don’t hesitate.
The latest release of SQLCipher for Android includes a high-priority fix to address a compatibility issue with an upcoming Android OS release. When the new Android version is released, most likely later this year, applications using older SQLCipher for Android versions may crash on first use of the library.
We have been working closely with Google to address the problem, which stems from changes to android::MemoryBase, a wrapper around the Android shared memory functions previously used in the native CursorWindow implementation. The new version of SQLCipher for Android eliminates the use of android::MemoryBase in CursorWindow in favor of allocated heap memory.
Google has confirmed that the latest version of SQLCipher for Android addresses the compatibility issue with the new Android OS version.
Since applications that continue to access the legacy shared memory function will break at some point in the future, Google has recently introduced a warning trigger on API usage in a recent AOSP commit [1].
As a result of this upcoming change, we strongly urge all developers using SQLCipher for Android to upgrade to the newest version. We do not have a specific release date from Google, so it’s important that applications update as soon as reasonably possible.
The latest SQLCipher for Android binaries can be found here [2].
https://android-review.googlesource.com/#/c/61890/
https://s3.amazonaws.com/sqlcipher/SQLCipher+for+Android+2.2.1.zip