CVE-2026-23965
Juneandgreen Sm-Crypto ≤ 0.4.0
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NSummary
CVE-2026-23965 is a high-severity Improper Verification of Cryptographic Signature (CWE-347) vulnerability in Juneandgreen Sm-Crypto. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Supply Chain Compromise (T1195); ranked at the 9th 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 SC-13 (Cryptographic Protection) and SI-7 (Software, Firmware, and Information Integrity) — 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-2026-23965 is a signature forgery vulnerability in the SM2 signature verification logic of the sm-crypto JavaScript library, which provides implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. The flaw affects versions of sm-crypto prior to 0.4.0 and is classified under CWE-347. It was published on 2026-01-22 with a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N), highlighting high integrity impact.
Remote attackers require no privileges or user interaction to exploit the vulnerability under default configurations. They can forge valid SM2 signatures for arbitrary public keys, potentially bypassing authentication or integrity checks in applications relying on the library. If the message space contains sufficient redundancy, attackers can fix the prefix of the associated message to satisfy specific formatting requirements, enabling targeted forgery.
The issue is patched in sm-crypto version 0.4.0. Security practitioners should upgrade to this version immediately. Further details, including the patch commit, are available at https://github.com/JuneAndGreen/sm-crypto/commit/85295a859d0766222d12ce2be3e6fce7b438b510, and the GitHub security advisory at https://github.com/JuneAndGreen/sm-crypto/security/advisories/GHSA-hpwg-xg7m-3p6m.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-3674
Vulnerability Data
sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A signature forgery vulnerability exists in the SM2 signature verification logic of sm-crypto prior to version 0.4.0. Under default configurations, an attacker can forge valid signatures for…
more
arbitrary public keys. If the message space contains sufficient redundancy, the attacker can fix the prefix of the message associated with the forged signature to satisfy specific formatting requirements. Version 0.4.0 patches the issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 14 hardening rules · 5 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Requiring cryptographic protection mechanisms forces correct signature verification to be implemented for data protection.
Mandating integrity verification tools directly requires proper cryptographic signature checking to detect unauthorized changes.
Protecting session authenticity requires correct verification of cryptographic signatures or equivalent mechanisms.
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.
Digital signatures are explicitly cited to protect integrity of data-at-rest, so proper verification directly mitigates the weakness.
Digital signatures are explicitly cited to protect integrity of data-in-transit, so proper verification directly mitigates the weakness.
Requires assessing authenticity and integrity of acquired assets, which commonly relies on signature verification but is limited to pre-acquisition.
Secure SDLC practices include code signing and signature verification requirements, addressing the weakness during development.
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.
Establishing approved cryptographic solutions and usage practices lowers the probability that signature-verification steps will be omitted or incorrectly implemented.
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-347
- 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-347
Oracle Linux 9 (2 rules)
- V-271525 OL 9 must have GPG signature verification enabled for all software repositories. prevents CWE-347
- V-271523 OL 9 must check the GPG signature of locally installed software packages before installation. prevents CWE-347
RHEL 7 (2 rules)
- V-204447 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository 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-347
- V-204448 The Red Hat Enterprise Linux operating system 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-347
RHEL 8 (1 rule)
- V-230264 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository 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-347
RHEL 9 (1 rule)
- V-257822 RHEL 9 must have GPG signature verification enabled for all software repositories. prevents CWE-347