CVE-2026-40069
Sgbett Bsv Ruby Sdk 0.1.0 – 0.8.2
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-40069 is a high-severity Improper Check for Unusual or Exceptional Conditions (CWE-754) vulnerability in Sgbett Bsv Ruby Sdk. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Service Stop (T1489); ranked at the 18th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-40069 affects the BSV Ruby SDK, a Ruby library for interacting with the BSV blockchain, in versions from 0.1.0 up to but not including 0.8.2. The vulnerability lies in the BSV::Network::ARC component's failure detection mechanism, which only recognizes REJECTED and DOUBLE_SPEND_ATTEMPTED as broadcast failures. Responses from ARC with txStatus values such as INVALID, MALFORMED, MINED_IN_STALE_BLOCK, or those containing ORPHAN in extraInfo or txStatus are incorrectly treated as successful transaction broadcasts. This flaw, rated at CVSS 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N) and mapped to CWE-754, can mislead applications that rely on broadcaster success signals.
Remote attackers require no privileges or user interaction to exploit this issue over the network. By submitting transactions that the BSV network rejects for the noted reasons, adversaries can trick vulnerable applications into believing the broadcasts succeeded, even though the transactions were never accepted. This enables integrity violations, such as applications proceeding with actions gated behind perceived successful broadcasts, potentially leading to flawed business logic or trust in invalid blockchain transactions.
The vulnerability is addressed in BSV Ruby SDK version 0.8.2, as detailed in the project's GitHub security advisory (GHSA-9hfr-gw99-8rhx), release notes, associated pull request, and fixing commit. Security practitioners should advise upgrading to 0.8.2 or later to properly handle all ARC failure statuses and prevent false positives in broadcast detection.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-20994
Vulnerability Data
BSV Ruby SDK is the Ruby SDK for the BSV blockchain. From 0.1.0 to before 0.8.2, BSV::Network::ARC's failure detection only recognises REJECTED and DOUBLE_SPEND_ATTEMPTED. ARC responses with txStatus values of INVALID, MALFORMED, MINED_IN_STALE_BLOCK, or any ORPHAN-containing extraInfo / txStatus are…
more
silently treated as successful broadcasts. Applications that gate actions on broadcaster success are tricked into trusting transactions that were never accepted by the network. This vulnerability is fixed in 0.8.2.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 7 hardening rules · 2 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation explicitly exercises unusual conditions to find missing or incorrect checks.
Input validation directly requires checking for unexpected or malformed conditions before they propagate.
Security engineering principles include structured handling of edge cases and exceptions during design.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure development practices directly require proper checks and handling for exceptional conditions throughout the SDLC.
Runtime monitoring of software and environments can detect adverse events triggered by unhandled exceptional conditions.
Generating logs of exceptions and errors enables detection of improper handling of unusual conditions.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development and acceptance verifies handling of error and exceptional conditions.
Logging can record unhandled exceptions but does not prevent the weakness itself.
Monitoring may detect symptoms of unhandled conditions but does not eliminate the root weakness.
Secure development life cycle mandates exception handling and input validation that directly prevent missing checks for unusual conditions.
Application security requirements explicitly call for handling of exceptional conditions and error paths.
Secure system architecture and engineering principles require robust error and exception handling mechanisms.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (2 rules)
- V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. prevents CWE-754
- V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-754
Oracle Linux 9 (1 rule)
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-754