As part of our Methodology, we ask:
Published code doesn’t help much if the app fails to compile.
We try to compile the published source code using the published build instructions into a binary. If that fails, we might try to work around issues but if we consistently fail to build the app, we give it this verdict and open an issue in the issue tracker of the provider to hopefully verify their app later.
The product cannot be independently verified. If the provider puts your funds at risk on purpose or by accident, you will probably not know about the issue before people start losing money. If the provider is more criminally inclined he might have collected all the backups of all the wallets, ready to be emptied at the press of a button. The product might have a formidable track record but out of distress or change in management turns out to be evil from some point on, with nobody outside ever knowing before it is too late.But we also ask:
Discontinued products or worse, products of providers that are not active anymore, are problematic, especially if they were not formerly reproducible and well audited to be self-custodial following open standards. If the provider hasn’t answered inquiries for a year but their server is still running or similar circumstances might get this verdict, too.
The Analysis ¶
This does not represent a full code review.
This app claims:
- Bitcoin (BTC) & Bitcoin Cash (BCH) support
- 100% control of your private keys
so it’s a self-custodial BTC wallet. And it’s also open source:
This wallet is a free and open source software. You can view the code on GitHub at http://github.com/blocktrail/blocktrail-wallet.
That’s great but can we reproduce the app?
On Google Play the “current version” is 4.4.7 and on GitHub we find a tag for
that.
The Readme.md also contains compile instructions. Let’s do this:
$ git clone https://github.com/blocktrail/blocktrail-wallet
$ cd blocktrail-wallet/
$ git checkout v4.4.7
$ docker run -it --volume $PWD:/mnt --workdir /mnt --rm beevelop/cordova bash
root@f74eea3c3d23:/mnt# npm install -g npm # make sure npm is latest version
root@f74eea3c3d23:/mnt# npm_config_engine_strict=false npm install -g ionic@4.3.1 cordova@8.1.2 gulp
root@f74eea3c3d23:/mnt# npm install
(node:39) ExperimentalWarning: The fs.promises API is experimental
npm ERR! code 1
npm ERR! path /mnt/node_modules/@sentry/cli
npm ERR! command failed
npm ERR! command sh -c node scripts/install.js
npm ERR! Error: Command failed: /mnt/node_modules/@sentry/cli/sentry-cli --version
npm ERR! error: Failed to load .sentryclirc file from the home folder.
npm ERR! caused by: Permission denied (os error 13)
npm ERR! A complete log of this run can be found in:
npm ERR! /root/.npm/_logs/2021-03-05T02_14_24_795Z-debug.log
so as .sentryclirc
apparently is a file that has to be in the home folder
with some sort of credentials, we probably can’t build the project without this
further step and conclude the app is not verifiable.
Apart from there being source code it is worth mentioning that the app was not updated since July 2019 and many 1* ratings complain about financial loss!
Do your own research!
Try out searching for "lost bitcoins", "stole my money" or "scammers" together with the wallet's name, even if you think the wallet is generally trustworthy. For all the bigger wallets you will find accusations. Make sure you understand why they were made and if you are comfortable with the provider's reaction.
If you find something we should include, you can create an issue or edit this analysis yourself and create a merge request for your changes.