Security readout for executives and security teams
Plain-English summary
CVE-2026-23967 affects the JavaScript sm-crypto library before version 0.3.14. A person who already has a valid SM2 signature for a message can create another valid-looking signature for that same message. This can undermine systems that treat each signature as unique proof of approval or identity.
Executive priority
Prioritize remediation for applications where SM2 signatures protect financial, legal, identity, or audit-sensitive actions. This is not reported as actively exploited in the provided sources, but the integrity impact is high and the fix is identified: upgrade to 0.3.14.
Technical view
The issue is signature malleability in sm-crypto SM2 signature verification, classified as CWE-347. It affects JuneAndGreen sm-crypto versions before 0.3.14. CVSS 3.1 is 7.5, network exploitable, low complexity, no privileges or user interaction, with high integrity impact. Version 0.3.14 patches the issue.
Likely exposure
Exposure is likely in JavaScript applications or services using sm-crypto below 0.3.14 for SM2 signature verification. Risk is higher where signatures authorize transactions, approvals, audit events, identity assertions, or anti-replay logic. Systems not using sm-crypto or not using SM2 verification are not indicated as affected by the provided sources.
Exploitation context
The CVE description states an attacker can derive a new valid signature for a previously signed message from an existing signature. The source bundle does not indicate active exploitation, public weaponization, or CISA KEV listing. Treat this as an integrity risk, especially for workflows relying on signature uniqueness.
Researcher notes
The available public detail is limited to the CVE record and GitHub advisory. Do not assume affected forks, other cryptographic libraries, or broader SM2 implementations are vulnerable without evidence. Focus validation on sm-crypto package usage before 0.3.14 and business logic depending on signature uniqueness.
Mitigation direction
- Upgrade sm-crypto to version 0.3.14 or later.
- Identify direct and transitive dependencies using sm-crypto.
- Prioritize systems using SM2 signatures for authorization or audit integrity.
- Review vendor advisory for any additional guidance.
- Retest signature-dependent business workflows after updating.
Validation and detection
- Check dependency manifests and lockfiles for sm-crypto versions below 0.3.14.
- Confirm deployed artifacts use the patched package version.
- Verify applications using SM2 verification were included in remediation scope.
- Run regression tests for SM2 signature verification behavior.
- Document any systems where upgrade is delayed and track vendor guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-347: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-23967 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/JuneAndGreen/sm-crypto/security/advisories/GHSA-qv7w-v773-3xqmCVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Verification of Cryptographic Signature
Improper Verification of Cryptographic Signature represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.