Aug 23, 2023

The following CVE has been published in relation to BX. https://nvd.nist.gov/vuln/detail/CVE-2023-39910 Libbitcoin developers have: * Removed the `seed` command from version3 (and master). * Tagged a new 3.8.0 release (without the command). * Replaced `bx seed` with `echo [user entropy]` in certain documentation examples. * Removed precompiled binaries for previous bx versions. * Submitted the two items of feedback below to MITRE (CVE maintainers). * Posted this notice to the libbitcoin Slack and mailing list. ---------------------------------------------------------------------------------- The libbitcoin open source team rejects the implication that the issue is of "bad cryptography" and accepts that people may have used the command in a manner not intended (and warned against). Consequently we have simply removed the command in updated version 3.8.0. All examples in the provided documentation have been updated to replace `bx seed` with `echo [user entropy]`. Precompiled binaries of older versions previously available for download have been removed. As such there is no longer any potential for the command to be misused in the current release. https://github.com/libbitcoin/libbitcoin-explorer/releases/tag/v3.8.0 https://github.com/libbitcoin/libbitcoin-explorer/wiki/bx-hd-new#example-4 https://github.com/libbitcoin/libbitcoin-explorer/wiki/Download-BX ---------------------------------------------------------------------------------- From the CVE Description: "...NOTE: the vendor's position is that there was sufficient documentation advising against "bx seed" but others disagree." The question is not of "sufficiency", but intent. The bx 3.x `seed` command was not intended for live wallet use. The warning against it is even referenced in the "Milk Sad" article. The fact that some people appear to have used the command for live wallet seeding implies that documentation may have been "insufficient", however it is ultimately impossible to force people to read, understand and respect documentation. In fact we have been advised by the authors of this CVE that the two parties identified in their research did not even read the documentation for the `seed` command - they assumed its behavior. It is a design goal that users provide entropy on the command line (or by parameter to any API that requires it), which is why the command is not necessary. It was provided as a convenient way to obtain properly formatted and sized (length, not strength) pseudo entropy for the vast majority of use cases. bx demonstrates C++ calling conventions and usage of many of the APIs exposed by the 9 other libraries, tying those calls to real-world scenarios in order to provide context and therefore better understanding of what are often difficult topics. bx is not a wallet - manual creation of live wallets using the "development toolkit" requires significant expertise and caution and is not advised. Suggested description: "The Bitcoin developer toolkit utility application Libbitcoin Explorer (bx) provides a pseudo entropy command not intended for live cryptocurrency wallet seeding, yet analysis implies that some users may have not heeded warnings against such use. This allows remote attackers to recover any wallet private keys generated from "bx seed" entropy output and steal funds. (Affected users need to move funds to a secure new cryptocurrency wallet.) NOTE: this was exploited in the wild in June and July 2023." https://github.com/libbitcoin/libbitcoin-explorer/wiki/Random-Numbers https://github.com/libbitcoin/libbitcoin-explorer/wiki/bx-cert-new https://github.com/libbitcoin/libbitcoin-explorer/wiki/bx-seed ----------------------------------------------------------------------------------