How severe is CVE-2023-39910?

CVE-2023-39910 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2023-39910 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-39910?

CVE-2023-39910 affects Libbitcoin Libbitcoin Explorer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-39910?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-39910 published?

CVE-2023-39910 was published on 2023-08-09 and last updated on 2026-06-17.

CVE-2023-39910

CVE-2023-39910 is a high-severity vulnerability in Libbitcoin Libbitcoin Explorer with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-338.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-338
Affected product: Libbitcoin Libbitcoin Explorer
Published: 2023-08-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-39910?: 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.
How severe is CVE-2023-39910?: CVE-2023-39910 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2023-39910 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-39910?: CVE-2023-39910 affects Libbitcoin Libbitcoin Explorer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-39910?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-39910 published?: CVE-2023-39910 was published on 2023-08-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:libbitcoin:libbitcoin_explorer:*:*:*:*:*:*:*:*

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