CVE-2021-20305

2021-04-0521:31:06

CWE-327

redhat

www.cve.org

nettle

flaw

signature verification

gost dsa

eddsa

ecdsa

elliptic curve cryptography

out-of-range scalars

incorrect results

invalid signature

assertion failure

validation

confidentiality

integrity

system availability

AI Score

8.2

Confidence

High

EPSS

0.01

Percentile

83.4%

JSON

A flaw was found in Nettle in versions before 3.7.2, where several Nettle signature verification functions (GOST DSA, EDDSA & ECDSA) result in the Elliptic Curve Cryptography point (ECC) multiply function being called with out-of-range scalers, possibly resulting in incorrect results. This flaw allows an attacker to force an invalid signature, causing an assertion failure or possible validation. The highest threat to this vulnerability is to confidentiality, integrity, as well as system availability.

CNA Affected

[
  {
    "product": "nettle",
    "vendor": "n/a",
    "versions": [
      {
        "status": "affected",
        "version": "nettle 3.7.2"
      }
    ]
  }
]