8.1
HIGH CVSS 3.1
CVE-2026-40070
bsv-sdk and bsv-wallet persist unverified certifier signatures in acquire_certificate (direct and issuance paths)
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.

INFO

Published Date :

April 9, 2026, 6:17 p.m.

Last Modified :

April 9, 2026, 6:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-40070 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
Solution
Update BSV Ruby SDK to verify signatures before storing certificates.
  • Update BSV Ruby SDK to version 0.8.2 or later.
  • Ensure all certificate signatures are verified.
  • Validate data received from certifier endpoints.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-40070 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-40070 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-40070 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-40070 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 09, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
    Added CWE CWE-347
    Added Reference https://brc.dev/52
    Added Reference https://github.com/sgbett/bsv-ruby-sdk/commit/4992e8a265fd914a7eeb0405c69d1ff0122a84cc
    Added Reference https://github.com/sgbett/bsv-ruby-sdk/issues/305
    Added Reference https://github.com/sgbett/bsv-ruby-sdk/pull/306
    Added Reference https://github.com/sgbett/bsv-ruby-sdk/security/advisories/GHSA-hc36-c89j-5f4j
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.