What is CVE-2026-23966?

CVE-2026-23966 is a critical-severity vulnerability in Juneandgreen Sm-Crypto, classified under Insufficient Verification of Data Authenticity. CVSS score: 9.1/10. Published 2026-01-22.

How severe is CVE-2026-23966?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Juneandgreen Sm-Crypto

CVE-2026-23966

sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A private key recovery vulnerability exists in the SM2 decryption logic of sm-crypto prior to version 0.3.14. By interacting with the SM2 decryption interface multiple times, an attacker can fully recover the private key within approximately several hundred interactions. Version 0.3.14 patches the issue.

EPSS: 0.002 (11.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Juneandgreen Sm-crypto — versions < 0.3.14

Weakness classification (CWE)

CWE-345 — Insufficient Verification of Data Authenticity

References

security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-23966?: CVE-2026-23966 is a critical-severity vulnerability in Juneandgreen Sm-Crypto, classified under Insufficient Verification of Data Authenticity. CVSS score: 9.1/10. Published 2026-01-22.
How severe is CVE-2026-23966?: Critical severity. CVSS v3 base score is 9.1 out of 10.