Vulnerability · Published Apr 9, 2026 · Assigned by GitHub_M
CVE-2026-40070bsv-sdk and bsv-wallet persist unverified certifier signatures in acquire_certificate (direct and issuance paths)
High 8.1
In plain English
A high-severity security flaw in bsv-ruby-sdk from sgbett. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| RubyGems | bsv-sdk | 0.8.2 | GHSA-hc36-c89j-5f4j |
| RubyGems | bsv-wallet | 0.3.4 | GHSA-hc36-c89j-5f4j |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| sgbett | bsv-ruby-sdk | >= 0.3.1, < 0.8.2 |
| sgbett | bsv-sdk | >= 0.3.1, < 0.8.2 |
| sgbett | bsv-wallet | >= 0.1.2, < 0.3.4 |
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
References
- https://github.com/sgbett/bsv-ruby-sdk/security/advisories/GHSA-hc36-c89j-5f4j x_refsource_CONFIRM
- https://github.com/sgbett/bsv-ruby-sdk/issues/305 x_refsource_MISC
- https://github.com/sgbett/bsv-ruby-sdk/pull/306 x_refsource_MISC
- https://github.com/sgbett/bsv-ruby-sdk/commit/4992e8a265fd914a7eeb0405c69d1ff0122a84cc x_refsource_MISC
- https://brc.dev/52 x_refsource_MISC