CVE-2026-22698

high

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.

References

https://github.com/RustCrypto/elliptic-curves/security/advisories/GHSA-w3g8-fp6j-wvqw

https://github.com/RustCrypto/elliptic-curves/pull/1600

https://github.com/RustCrypto/elliptic-curves/commit/e4f77788130d065d760e57fb109370827110a525

https://github.com/RustCrypto/elliptic-curves/commit/4781762f23ff22ab34763410f648128055c93731

https://crates.io/crates/sm2/0.14.0-rc.0

https://crates.io/crates/sm2/0.14.0-pre.0

Details

Source: Mitre, NVD

Published: 2026-01-10

Updated: 2026-01-10

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: High

CVSS v4

Base 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

Severity: High

EPSS

EPSS: 0.00029