CVEvulnerability
CVE-2023-39910
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2023-08-09
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- Weaknesses
- CWE-338
Description
The cryptocurrency wallet entropy seeding mechanism used in Libbitcoin Explorer 3.0.0 through 3.6.0 is weak, aka the Milk Sad issue. The use of an mt19937 Mersenne Twister PRNG restricts the internal entropy to 32 bits regardless of settings. 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: the vendor's position is that there was sufficient documentation advising against "bx seed" but others disagree. NOTE: this was exploited in the wild in June and July 2023.
Affected configurations
• libbitcoin libbitcoin explorer (>= 3.0.0 <= 3.6.0)
Related
Weakness · CWE (1)
- CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) weakness
References
- https://github.com/libbitcoin/libbitcoin-explorer/blob/20eba4db9a8a3476949d6fd08a589abda7fde3e3/src/commands/seed.cpp#L44 Third Party Advisory
- https://github.com/libbitcoin/libbitcoin-explorer/blob/20eba4db9a8a3476949d6fd08a589abda7fde3e3/src/utility.cpp#L78 Third Party Advisory
- https://github.com/libbitcoin/libbitcoin-explorer/wiki/CVE-2023-39910 github.com
- https://github.com/libbitcoin/libbitcoin-system/blob/a1b777fc51d9c04e0c7a1dec5cc746b82a6afe64/src/crypto/pseudo_random.cpp#L66C12-L78 Third Party Advisory
- https://milksad.info/disclosure.html Third Party Advisory
- https://news.ycombinator.com/item?id=37054862 Third Party Advisory
- https://github.com/libbitcoin/libbitcoin-explorer/blob/20eba4db9a8a3476949d6fd08a589abda7fde3e3/src/commands/seed.cpp#L44 Third Party Advisory
- https://github.com/libbitcoin/libbitcoin-explorer/blob/20eba4db9a8a3476949d6fd08a589abda7fde3e3/src/utility.cpp#L78 Third Party Advisory
- https://github.com/libbitcoin/libbitcoin-explorer/wiki/CVE-2023-39910 github.com
- https://github.com/libbitcoin/libbitcoin-system/blob/a1b777fc51d9c04e0c7a1dec5cc746b82a6afe64/src/crypto/pseudo_random.cpp#L66C12-L78 Third Party Advisory
- https://milksad.info/disclosure.html Third Party Advisory
- https://news.ycombinator.com/item?id=37054862 Third Party Advisory