---
title: "CVE-2026-23966: sm-crypto Affected by Private Key Recovery in SM2-PKE"
url: https://erroneo.us/security/cve/CVE-2026-23966/
description: "CVE-2026-23966 (sm-crypto (npm)): sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A private key…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-01-22
date_modified: 2026-01-22
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-23966"
kev: false
cvss: 9.1
epss: 0.00232
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-23966: sm-crypto Affected by Private Key Recovery in SM2-PKE

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.2% , percentile 13: FIRST’s model estimates a 0.2% chance of exploitation activity in the next 30 days, higher than 13% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes sm-crypto (npm) < 0.3.14, fixed in 0.3.14 . Check your lockfile, including transitive dependencies.

## What it is

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.

## Affected packages

- npm `sm-crypto` < 0.3.14 → fixed: 0.3.14

## Affected products (CVE record)

- JuneAndGreen sm-crypto: < 0.3.14

## Severity

- GitHub_M CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`
- GitHub CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.23% probability of exploitation activity in the next 30 days; percentile 13.

## Sources

- [GitHub Advisory GHSA-pgx9-497m-6c4v](https://github.com/advisories/GHSA-pgx9-497m-6c4v)
- [CVE.org record CVE-2026-23966](https://www.cve.org/CVERecord?id=CVE-2026-23966)
- [NVD entry CVE-2026-23966](https://nvd.nist.gov/vuln/detail/CVE-2026-23966)
- [github.com](https://github.com/JuneAndGreen/sm-crypto/security/advisories/GHSA-pgx9-497m-6c4v)
- [github.com](https://github.com/JuneAndGreen/sm-crypto/commit/b1c824e58fdf1eaa73692c124a095819a8c45707)

---
Source page: https://erroneo.us/security/cve/CVE-2026-23966/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt