RustCrypto: Elliptic Curves is general purpose Elliptic Curve Cryptography (ECC) support, including types and traits for representing various elliptic curve forms, scalars, points, and public/secret keys composed thereof. In versions 0.14.0-pre.0 and 0.14.0-rc.0, a critical vulnerability exists in the SM2 Public Key Encryption (PKE) implementation where the ephemeral nonce k is generated with severely reduced entropy. A unit mismatch error causes the nonce generation function to request only 32 bits of randomness instead of the expected 256 bits. This reduces the security of the encryption from a 128-bit level to a trivial 16-bit level, allowing a practical attack to recover the nonce k and decrypt any ciphertext given only the public key and ciphertext. This issue has been patched via commit e4f7778.

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Affected Vendors & Products

Vendors Products
Rustcrypto
  • Elliptic-curves

No data.

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References
Link Providers
https://crates.io/crates/sm2/0.14.0-pre.0 cve-icon cve-icon
https://crates.io/crates/sm2/0.14.0-rc.0 cve-icon cve-icon
https://github.com/RustCrypto/elliptic-curves/commit/4781762f23ff22ab34763410f648128055c93731 cve-icon cve-icon
https://github.com/RustCrypto/elliptic-curves/commit/e4f77788130d065d760e57fb109370827110a525 cve-icon cve-icon
https://github.com/RustCrypto/elliptic-curves/pull/1600 cve-icon cve-icon
https://github.com/RustCrypto/elliptic-curves/security/advisories/GHSA-w3g8-fp6j-wvqw cve-icon cve-icon
History

Mon, 12 Jan 2026 17:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Mon, 12 Jan 2026 14:45:00 +0000

Type Values Removed Values Added
First Time appeared Rustcrypto
Rustcrypto elliptic-curves
Vendors & Products Rustcrypto
Rustcrypto elliptic-curves

Sat, 10 Jan 2026 05:30:00 +0000

Type Values Removed Values Added
Description RustCrypto: Elliptic Curves is general purpose Elliptic Curve Cryptography (ECC) support, including types and traits for representing various elliptic curve forms, scalars, points, and public/secret keys composed thereof. In versions 0.14.0-pre.0 and 0.14.0-rc.0, a critical vulnerability exists in the SM2 Public Key Encryption (PKE) implementation where the ephemeral nonce k is generated with severely reduced entropy. A unit mismatch error causes the nonce generation function to request only 32 bits of randomness instead of the expected 256 bits. This reduces the security of the encryption from a 128-bit level to a trivial 16-bit level, allowing a practical attack to recover the nonce k and decrypt any ciphertext given only the public key and ciphertext. This issue has been patched via commit e4f7778.
Title RustCrypto SM2-PKE has 32-bit Biased Nonce Vulnerability
Weaknesses CWE-331
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-01-10T05:17:19.993Z

Updated: 2026-01-12T16:48:30.706Z

Reserved: 2026-01-08T19:23:09.856Z

Link: CVE-2026-22698

cve-icon Vulnrichment

Updated: 2026-01-12T16:48:28.067Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-01-10T06:15:52.220

Modified: 2026-01-13T14:03:18.990

Link: CVE-2026-22698

cve-icon Redhat

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