VULNERABILITY INTELLIGENCE

CVE-2023-1732

CVSS score5.3 MEDIUM
EPSS probability0.39%
CISA KEVNot currently listed
Published2023-05-10
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N

Description

When sampling randomness for a shared secret, the implementation of Kyber and FrodoKEM, did not check whether crypto/rand.Read() returns an error. In rare deployment cases (error thrown by the Read() function), this could lead to a predictable shared secret. The tkn20 and blindrsa components did not check whether enough randomness was returned from the user provided randomness source. Typically the user provides crypto/rand.Reader, which in the vast majority of cases will always return the right number random bytes. In the cases where it does not, or the user provides a source that does not, the blinding for blindrsa is weak and integrity of the plaintext is not ensured in tkn20.

Weakness classification

  • cna@cloudflare.com: CWE-20
  • nvd@nist.gov: CWE-755

Primary references