How severe is CVE-2026-40070?

CVE-2026-40070 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-40070 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-40070?

CVE-2026-40070 primarily affects Sgbett Bsv-wallet. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-40070?

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.

Does CVE-2026-40070 have an EU (EUVD) identifier?

Yes. CVE-2026-40070 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20996.

When was CVE-2026-40070 published?

CVE-2026-40070 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-40070

CVE-2026-40070 is a high-severity vulnerability in Sgbett Bsv-wallet with a CVSS 3.x base score of 8.1. 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-347.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20996
Weakness: CWE-347
Affected product: Sgbett Bsv-wallet
Published: 2026-04-09
Last modified: 2026-06-17

Description

BSV Ruby SDK is the Ruby SDK for the BSV blockchain. From 0.3.1 to before 0.8.2, BSV::Wallet::WalletClient#acquire_certificate persists certificate records to storage without verifying the certifier's signature over the certificate contents. In acquisition_protocol: 'direct', the caller supplies all certificate fields (including signature:) and the record is written to storage verbatim. In acquisition_protocol: 'issuance', the client POSTs to a certifier URL and writes whatever signature the response body contains, also without verification. An attacker who can reach either API (or who controls a certifier endpoint targeted by the issuance path) can forge identity certificates that subsequently appear authentic to list_certificates and prove_certificate.

Frequently asked questions

What is CVE-2026-40070?: BSV Ruby SDK is the Ruby SDK for the BSV blockchain. From 0.3.1 to before 0.8.2, BSV::Wallet::WalletClient#acquire_certificate persists certificate records to storage without verifying the certifier's signature over the certificate contents. In acquisition_protocol: 'direct', the caller supplies all certificate fields (including signature:) and the record is written to storage verbatim. In acquisition_protocol: 'issuance', the client POSTs to a certifier URL and writes whatever signature the response body contains, also without verification. An attacker who can reach either API (or who controls a certifier endpoint targeted by the issuance path) can forge identity certificates that subsequently appear authentic to list_certificates and prove_certificate.
How severe is CVE-2026-40070?: CVE-2026-40070 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-40070 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-40070?: CVE-2026-40070 primarily affects Sgbett Bsv-wallet. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-40070?: 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.
Does CVE-2026-40070 have an EU (EUVD) identifier?: Yes. CVE-2026-40070 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20996.
When was CVE-2026-40070 published?: CVE-2026-40070 was published on 2026-04-09 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:sgbett:bsv-wallet:*:*:*:*:*:ruby:*:*
cpe:2.3:a:sgbett:bsv_ruby_sdk:*:*:*:*:*:ruby:*:*

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